Modified oilseed material

ABSTRACT

A modified oilseed material formed from oilseed-based material is described. The modified oilseed material can be utilized in a variety of nutritional applications, including the preparation of protein supplemented food products such as beverages, processed meats, frozen desserts, confectionery products, dairy-type products, and cereal grain products. The modified oilseed material typically includes at least 85 wt. % protein (dry solids basis), at least about 40% of the modified oilseed material has an apparent molecular weight of greater than 300 kDa, and/or a MW 50  of at least about 200 kDa.

RELATED APPLICATION

This application is a continuation-in-part of application Ser. No.09/717,923 entitled “Process for Producing Oilseed Protein Products,”filed Nov. 21, 2000, which is incorporated by reference herein.

BACKGROUND

Modified oilseed materials are used as food additives for enhancingtexture and other functional characteristics of various food products aswell as a source of protein. The use of modified oilseed materialsparticularly modified soybean materials may be limited in someinstances, however, due to their beany flavor and tan-like color. It isstill unclear exactly which components are responsible for the flavorand color characteristics of oilseeds, though a variety of compounds aresuspected of causing these characteristics. Among these are aliphaticcarbonyls, phenolics, volatile fatty acids and amines, esters andalcohols.

There are extensive reports of processes used for the isolation,purification and improvement of the nutritional quality and flavor ofoilseed materials, particularly soybean materials. Soybean protein inits native state is unpalatable and has impaired nutritional quality dueto the presence of phytic acid complexes which interfere with mammalianmineral absorption, and the presence of antinutritional factors whichinterfere with protein digestion in mammals. The reported methodsinclude the destruction of the trypsin inhibitors by heat treatment aswell as methods for the removal of phytic acid. A wide variety ofattempts to improve the yield of protein secured as purified isolaterelative to that contained in the soybean raw material have also beendescribed.

Many processes for improving soy protein flavor involve the applicationof heat, toasting, alcohol extraction and/or enzyme modification. Thesetypes of processes often result in substantial protein denaturation andmodification, thereby substantially altering the product'sfunctionality. In addition, these processes can promote interactionsbetween proteins with lipid and carbohydrate constituents and theirdecomposition products. These types of reactions can reduce the utilityof soy proteins in food products, especially in those that requirehighly soluble and functional proteins, as in dairy foods and beverages.

Commercial soy protein concentrates, which are defined as soy proteinproducts having at least 70% by weight protein (dry solids basis or“dsb”), are generally produced by removing soluble sugars, ash and someminor constituents. The sugars are commonly removed by extracting with:(1) aqueous alcohol; (2) dilute aqueous acid; or (3) water, after firstinsolubilizing the protein with moist heating. These processes generallyproduce soy protein products with a distinctive taste and color.

Soy protein isolates are defined as products having at least 90% byweight protein (dsb). Commercial processes for producing soy proteinisolates are generally based on acid precipitation of protein. Thesemethods of producing, typically include (1) extracting the protein fromsoy flakes with water at an alkaline pH and removing solids from theliquid extract; (2) subjecting the liquid extract to isoelectricprecipitation by adjusting the pH of the liquid extract to the point ofminimum protein solubility to obtain the maximum amount of proteinprecipitate; and (3) separating precipitated protein curd fromby-product liquid whey. This type of process, however, still tends toproduce a protein product with a distinctive taste and color.

A number of examples of processes for producing concentrated soy proteinproducts using membrane filtration technology have been reported. Due toa number of factors including cost, efficiency and/or productcharacteristics, however, membrane-based purification approaches havenever experienced widespread adoption as commercial processes. Theseprocesses can suffer from one or more disadvantages, such as reducedfunctional characteristics in the resulting protein product and/or theproduction of a product which has an “off” flavor and/or an off-colorsuch as a dark cream to light tan color. Membrane-based processes canalso be difficult to operate under commercial production conditions dueto problems associated with bacterial contamination and fouling of themembranes. Bacterial contamination can have undesirable consequences forthe flavor of the product.

SUMMARY

A modified oilseed material with desirable flavor and/or colorcharacteristics derived from oilseed material, such as defatted soybeanwhite flakes or soybean meal, is described herein. The modified oilseedmaterial is particularly suitable for use as a protein source forincorporation into foods for human and/or animal consumption.

The present modified oilseed material can be produced by amembrane-based purification process which typically includes anextraction step to solubolize proteinaceous material present in anoilseed material. It may be desirable to conduct the extraction as acontinuous, multistage process, e.g., a countercurrent extraction.

The modified oilseed material can commonly be produced by a processwhich includes an extraction step to solubilize proteinaceous materialpresent in an oilseed material. The process uses one or more microporousmembranes to separate and concentrate protein from the extract. It isgenerally advantageous to use a microporous membrane which has a filtersurface with a relatively low contact angle, e.g., no more than about 40degrees. The process commonly utilizes either relatively large poreultrafiltration membranes (e.g., membranes with a molecular weightcut-off (“MWCO”) of about 25,000 to 500,000) or microfiltrationmembranes with pore sizes up to about 1.5μ. When microfiltrationmembranes are employed, those with pore sizes of no more than about 1.0μand, more desirably, no more than about 0.5μ are particularly suitable.Herein, the term “microporous membrane” is used to refer toultrafiltration membranes and microfiltration membranes collectively. Byemploying such relatively large pore microporous membranes, the membranefiltration operation in the present process can be carried out usingtransmembrane pressures of no more than about 100 psig, desirably nomore than about 50 psig, and more commonly in the range of 10-20 psig.

The modified oilseed material formed by the present method can be usedto produce protein supplemented food products. The modified oilseedmaterial can have a variety of characteristics that make it suitable foruse as a protein source for incorporation into food products. A suitablemodified oilseed material may include at least about 85 wt. % (dsb)protein, preferably at least about 90 wt. % (dsb) protein, and have oneor more of the following characteristics: a MW₅₀ of at least about 200kDa; at least about 40% of the material has an apparent molecular weightof greater than 300 kDa; at least about 40 wt. % of the protein in a 50mg sample may be soluble in 1.0 mL water at 25° C.; a turbidity factorof no more than about 0.95; a 13.5% aqueous solution forms a gel havinga breaking strength of no more than about 25 g; an NSI of at least about80; at least about 1.4% cysteine as a percentage of total protein; aGardner L value of at least about 85; a substantially bland taste; aviscosity slope of at least about 10 cP/min; an EOR of no more thanabout 0.75 mL; a melting temperature of at least about 87° C.; a latentheat of at least about 5 joules/g; a ratio of sodium ions to a totalamount of sodium, calcium and potassium ions of no more than 0.5; nomore than about 7000 mg/kg (dsb) sodium ions; and a bacteria load of nomore than about 50,000 cfu/g.

A particularly desirable modified oilseed material formed by the presentmethod which may be used to produce a protein supplemented food productmay include at least about 85 wt. % (dsb) protein, preferably at leastabout 90 wt. % (dsb) protein, and meet one or more of the followingcriteria: a MW₅₀ of at least about 400 kDa; at least about 60% of thematerial has an apparent molecular weight of greater than 300 kDa; atleast about 40 wt. % of the protein in a 50 mg sample may be soluble in1.0 mL water at 25° C.; a turbidity factor of no more than about 0.95; a13.5% aqueous solution forms a gel having a breaking strength of no morethan about 25 g; an NSI of at least about 80; at least about 1.5%cysteine as a percentage of total protein; a Gardner L value of at leastabout 85; a substantially bland taste; a viscosity slope of at leastabout 50 cP/min; an EOR of no more than about 0.5 mL; a meltingtemperature of at least about 87° C.; a latent heat of at least about 5joules/g; a ratio of sodium ions to a total amount of sodium, calciumand potassium ions of no more than 0.5; no more than about 7000 mg/kg(dsb) sodium ions; and a bacteria load of no more than about 50,000cfu/g.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a schematic of one example of a system which may be used toproduce a modified oilseed material according to the present method.

FIG. 2 shows a plot of the results of gel strength tests of fourexamples of modified oilseed material formed by the present method—LH(Ex. 1), LL (Ex. 2), HH (Ex. 3) and HL (Ex. 4).

FIG. 3 shows a photograph of test tubes containing suspensions of 5%(w/w) soy protein isolates in 5% (w/w) sucrose solutions immediatelyafter settling for 16 hours. The following labeling scheme was used forthe tubes—LH (Ex. 1), LL (Ex. 2), HH (Ex. 3), HL (Ex. 4), PTI760 (Supro™760) and PTI70 (Supro™ 670).

FIG. 4 shows a photograph of test tubes containing suspensions of 5%(w/w) soy protein isolates in 5% (w/w) sucrose solutions immediatelyafter remixing the solutions photographed in FIG. 3. The followinglabeling scheme was used for the tubes—LH (Ex. 1), LL (Ex. 2), HH (Ex.3), HL (Ex. 4), PTI760 (Supro™ 760) and PTI70 (Supro™ 670).

FIG. 5 depicts a HPLC trace showing the molecular weight profile of thepH 6.8 soluble material in a crude extract obtained from untoasted,defatted soy flakes (obtained by extraction of the soy flakes by themethod described in Example 1).

FIG. 6 depicts a HPLC trace showing the molecular weight profile of amodified oilseed material formed by the method described in Example 1.

FIG. 7 shows a differential scanning calorimetry scan of a modifiedoilseed material formed by the method described in Example 1.

FIG. 8 shows a differential scanning calorimetry scan of a modifiedoilseed material formed by the method described in Example 2.

FIG. 9 shows a plot illustrating the molecular weight of a modifiedoilseed material formed by the method described in Example 6 and themolecular weight of Supro™ 425.

FIG. 10 shows a plot illustrating viscosity as a function of temperaturefor a modified oilseed material formed by the method described inExample 2.

FIG. 11 shows a plot illustrating viscosity as a function of temperaturefor Supro™ 515.

DETAILED DESCRIPTION

The modified oilseed material provided by the present method generallyhas a high protein content as well being light colored and havingdesirable flavor characteristics. The modified oilseed material can havea variety of other characteristics that make it suitable for use as aprotein source for incorporation into foods for human and/or animalconsumption.

The modified oilseed material can commonly be produced by a processwhich includes an extraction step to solubilize proteinaceous materialpresent in an oilseed material and a subsequent purification of theextract using one or more microporous membranes to remove carbohydrates,salts and other non-protein components. Very often, the extract isclarified prior to membrane purification by at least removing asubstantial amount of the particulate material present in the suspensionproduced by the extraction procedure.

The process described herein uses one or more microporous membranes toseparate and concentrate protein from an oilseed extract. It isgenerally advantageous to use a microporous membrane which has a filtersurface with a relatively low contact angle, e.g., no more than about 40degrees. Microporous membranes with even lower contact angles, e.g.,with filter surfaces having a contact angle of no more than about 30degrees and in some instances of no more than about 15 degrees, areparticularly suitable for use in the present method. The processcommonly utilizes either relatively large pore ultrafiltration membranes(e.g., membranes with a molecular weight cut-off (“MWCO”) of at leastabout 30,000) or microfiltration membranes with pore sizes up to about2μ.

Source of Oilseed Material

The starting material employed in the present method generally includesmaterial derived from defatted oilseed material, although other forms ofoilseed based material may be employed. The fat may be substantiallyremoved from dehusked oilseeds by a number of different methods, e.g.,by simply pressing the dehusked seeds or by extracting the dehuskedseeds with an organic solvent, such as hexane. The defatted oilseedmaterial which is employed in preferred embodiments of the presentprocess typically contains no more than about 3 wt. % and, preferably,no more than about 1 wt. % fat. The solvent extraction process istypically conducted on dehusked oilseeds that have been flattened intoflakes. The product of such an extraction is referred to as an oilseed“white flake.” For example, soybean white flake is generally obtained bypressing dehusked soybeans into a flat flake and removing a substantialportion of the residual oil content from the flakes by extraction withhexane. The residual solvent can be removed from the resulting whiteflake by a number of methods. In one procedure, the solvent is extractedby passing the oilseed white flake through a chamber containing hotsolvent vapor. Residual hexane can then be removed from soybean whiteflakes by passage through a chamber containing hexane vapor at atemperature of at least about 75° C. Under such conditions, the bulk ofthe residual hexane is volatilized from the flakes and can subsequentlybe removed, e.g., via vacuum. The material produced by this procedure isreferred to as flash desolventized oilseed white flake. The flashdesolventized oilseed white flake is then typically ground to produce agranular material (meal). If desired, however, the flash desolventizedoilseed white flake may be used directly in the present method.

Another defatted oilseed derived material which is suitable for use inthe present process is derived from material obtained by removing thehexane from the oilseed white flake by a process referred to astoasting. In this process, the hexane extracted oilseed white flakes arepassed through a chamber containing steam at a temperature of at leastabout 105° C. This causes the solvent in the flakes to volatilize and becarried away with the steam. The resulting product is referred to astoasted oilseed flake. As with flash desolventized oilseed white flake,toasted oilseed flake may be used directly in the present method or maybe ground into a granular material prior to extraction.

While the desolventized oilseed white flake may be used directly in theextraction step, more commonly the desolventized flake is ground to ameal prior to being employed as starting material for the extraction.Oilseed meals of this type, such as soybean meal, are used in a widevariety of other applications and are readily available from commercialsources. Other examples of oilseed materials which are suitable for usein the culture medium include canola meal, sunflower meal, cottonseedmeal, peanut meal, lupin meal and mixtures thereof. Oilseed materialsderived from defatted soybean and/or defatted cottonseed areparticularly suitable for use in the present method since such materialshave a relatively high protein content. It is important to note thatalthough many of the examples and descriptions herein are applied to amodified soybean material, the present method and material should not beconstrued to be so limited, and may be applied to other grains andoilseeds.

Extraction of Oilseed Material

The extraction of the protein fraction from oilseed material can becarried out under a variety of conditions using conventional equipment.Among the factors which affect the choice of process parameters andequipment are the efficiency of the extraction, effects on the qualityof the protein in the extract and minimization of the environmentalimpact of the process. For cost and environmental reasons, one oftenwould like to reduce the volume of water used in the process. Theprocess parameters are also generally selected so as to minimize thedegradation of protein, e.g., via indigenous enzymes and/or chemicalreactions, as well as to avoid substantial bacterial contamination ofthe extract.

A variety of reactor configurations including stirred tank reactors,fluidized bed reactors, packed bed reactors may be employed in theextraction step. For example, the entire extraction reaction may beperformed in a single vessel having appropriate mechanisms to controlthe temperature and mixing of the medium. Alternatively, the extractionmay be carried out in multiple stages performed in separate reactionvessels (see, e.g., the process system illustrated in FIG. 1).

As is common with many processes, the optimization of the variousobjectives typically requires a balancing in the choice of processparameters. For example, in order to avoid substantial chemicaldegradation of the protein, the extraction may be run at a relativelylow temperature, e.g., about 15° C. to 40° C. and preferably about 20°C. to 35° C. Such temperatures, however, can be quite conducive tobacterial growth so that it may be best to minimize extraction timesand/or conduct subsequent process operations at higher temperatures toreduce bacterial growth.

Alternately, the extraction may be run at slightly higher temperatures,e.g., 50° C. to 60° C., to reduce the chances of bacterialcontamination. While this can reduce bacterial growth, the increasedtemperature can exacerbate potential problems due to chemicaldegradation of proteinaceous material. Thus, as for the extraction runat closer to room temperature, when the extraction is carried out at 50°C. to 60° C., it is generally desirable to complete the extraction asrapidly as possible in order minimize degradation of protein. When theextraction is run at temperatures between about 20° C. and 60° C., ithas generally been found that extraction times of one to two hours aresufficient to allow high recoveries of protein while avoidingsignificant protein degradation and/or bacterial contamination. Whenhigher temperatures are used, e.g., 50° C. to 60° C., it has been foundthat the extraction times of no more than about thirty minutes arecommonly sufficient to allow high recoveries of protein while avoidingsignificant protein degradation and/or bacterial contamination. Use ofhigher temperatures is generally avoided since substantial exposure totemperatures of 60° C. and above can lead to protein solutions whichhave a tendency to gel during processing.

Although oilseed materials have been extracted under both acidic andbasic conditions to obtain their proteinaceous material, the presentmethod typically includes an extraction under basic conditions, e.g.,using an alkaline solution having a pH of about 7.5 to about 10. Veryoften, the extraction is conducted by contacting the oilseed materialwith an aqueous solution containing a set amount of base, such as sodiumhydroxide, potassium hydroxide, ammonium hydroxide and/or calciumhydroxide, and allowing the pH to slowly decrease as the base isneutralized by substances extracted out of the solid oilseed material.The initial amount of base is typically chosen so that at the end of theextraction operation the extract has a desired pH value, e.g., a pHwithin the range of 8.0 to 9.5. Alternately, the pH of the aqueous phasecan be monitored (continuously or at periodic time intervals) during theextraction and base can be added as needed to maintain the pH at adesired value.

When the extraction is carried out as a single stage operation, thespent oilseed material is generally washed at least once with water oralkaline solution to recover proteinaceous material which may have beenentrained in the solids fraction. The washings may either be combinedwith the main extract for further processing or may be used in theextraction of a subsequent batch of oilseed material.

The extraction operation commonly produces a mixture of insolublematerial in an aqueous phase which includes soluble proteinaceousmaterial. The extract may be subjected directly to separation viamembrane filtration. In most cases, however, the extract is firstclarified by removing at least a portion of the particulate matter fromthe mixture to form a clarified extract. Commonly, the clarificationoperation removes a significant portion and, preferably, substantiallyall of the particulate material. Clarification of the extract canenhance the efficiency of the subsequent membrane filtration operationand help avoid fouling problems with the membranes used in thatoperation.

The clarification can be carried out via filtration and/or a relatedprocess (e.g., centrifugation) commonly employed to remove particulatematerials from the aqueous suspensions. Such processes do not, however,generally remove much of the soluble materials and thus the solubilizedprotein remains in the aqueous phase for further purification viamembrane filtration. Because of the desire to achieve a high overallprotein yield, the clarification step typically does not make use offiltration aids such as flocculants which could adsorb solubleproteinaceous material.

As depicted in FIG. 1, one suitable method of conducting the extractionand clarification operations employs a series of extraction tanks anddecanter centrifuges to carry out a multi-stage counter currentextraction process. This type of system permits highly efficientextractions to be carried out with a relatively low water to flakeratio. For example, this type of system can efficiently carry outextractions where the weight ratio of the aqueous extraction solution tothe oilseed material in each phase is in the range of 6:1 to 10:1. Useof low water to flake ratios can enable the production of an oilseedextract which contains a relatively high concentration of dissolvedsolids, e.g., dissolved solids concentrations of 5 wt. % or higher andthe production of extracts with at least about 7 wt. % solids is notuncommon. The use of low water to flake ratios and more concentratedextracts allows the process to be run in a system with lower volumecapacity requirements, thereby decreasing demands on capital costsassociated with the system.

If the system requirements in a particular instance do not includesignificant restrictions on overall volume, the extraction process maybe carried using higher water to flake ratios. Where relatively highwater to flake ratios are employed in the extraction operation, e.g.,ratios of 20:1 to 40:1, it may be more convenient to carry out theextraction in a single stage. While these types of water to flake ratioswill require systems capable of handling larger volumes of fluids (perpound of starting oilseed material), the higher dilution factor in theprotein extraction can decrease the potential for fouling themicroporous membrane(s) used in the membrane filtration operation.

Membrane Filtration

Extract liquor is transferred from the extraction system to a membraneseparation system, generally by first introducing clarified extract intoa membrane feed tank. The extract liquor commonly contains about4.0-5.0% soluble protein and about 1.5-2.0% dissolved non-proteinmaterial. One purpose of the microfiltration operation is to separateprotein from non-protein material. This can be accomplished bycirculating the extract liquor through a set of microfiltrationmembranes. Water and the non-protein materials pass through the membraneas permeate while most of the protein is retained in the circulatingstream (“retentate”). The protein-containing retentate is typicallyallowed to concentrate by about a 2.5-3× factor (e.g., concentration of30 gallons of incoming crude extract by a 3× factor produces 10 gallonsof retentate). The concentration factor can be conveniently monitored bymeasure the volume of permeate passing through the membranes. Membraneconcentration of the extract by a 3× factor generally produces aretentate stream with dissolved solids containing at least about 80 wt.% protein (dsb). In order to increase the protein concentration to 90wt. %, two 1:1 diafiltrations are typically carried out. In adiafiltration operation, water is added to the concentrated retentateand then removed through the microporous membranes. This can be carriedout in the manner described above or, in an alternate embodiment of thepresent method, the diafiltration can be carried out at the initialstage of the membrane filtration, e.g., by continuously adding water tothe incoming extract in a feed tank so as to substantially maintain theoriginal volume.

The membrane filtration operation typically produces a retentate whichis concentrated by at least a 2.5× factor, i.e., passing a volume of theextract through the filtration system produces a protein-enrichedretentate having a volume of no more than about 40% of the originalextract volume. The output from the membrane filtration operationgenerally provides a protein-enriched retentate which includes at leastabout 10 wt. % protein, and protein concentrations of 12 to 14 wt. % arereadily attained.

For environmental and efficiency reasons, it is generally desirable torecover as much of the water from the membrane permeates as possible andrecycle the recovered water back into the process. This decreases theoverall hydraulic demand of the process as well as minimizing the volumeof effluent discharged by the process. Typically, the diafiltrationpermeate is combined with the permeate from the concentration phase ofthe membrane filtration. The bulk of the water in the combined permeatecan be recovered by separating the combined permeate with a reverseosmosis (“RO”) membrane into an RO retentate and an RO permeate. ROseparation can produce a permeate that is essentially pure water. Thiscan be recycled back into earlier stages of the process. For example,the RO permeate can be used in an aqueous solution for extracting theoilseed material. The RO permeate can also be utilized in adiafiltration operation by diluting protein-enriched retentate with anaqueous diluent which includes the RO permeate.

The present process uses a membrane filtration system with one or moremicroporous membranes to separate and concentrate protein from theextract. It is generally advantageous to use a microporous membranewhich has a filter surface with a relatively low contact angle, e.g., nomore than about 40 degrees, as such membranes can provide efficientseparation while exhibiting good resistance to fouling. Microporousmembranes with even lower filter surface contact angles (i.e., surfaceshaving greater hydrophilicity) are particularly suitable for use in thepresent process. Such membranes may have a filter surface with a contactangle of 25 degrees or less and some membranes may have a filter surfacecontact angle of no more than about 10 degrees.

As used herein, the term “contact angle” refers to contact angles ofsurfaces measured using the Sessile Drop Method. This is an opticalcontact angle method used to estimate the wetting property of alocalized region on a surface. The angle between the baseline of a dropof water (applied to a flat membrane surface using a syringe) and thetangent at the drop boundary is measured. An example of a suitableinstrument for measuring contact angles is a model DSA 10 Drop ShapeAnalysis System commercially available from Kruss.

The membranes should be capable of retaining a high percentage of themedium and high molecular weight protein components present in theextract while allowing water and other components to pass through themembrane. The membrane filtration operation commonly utilizes eitherrelatively large pore ultrafiltration membranes (e.g., membranes with amolecular weight cut-off (“MWCO”) of at least about 30,000) ormicrofiltration membranes with pore sizes up to about 1.5μ. Low contactangle microfiltration membranes with MWCOs of 25,000 to 200,000 areparticularly suitable for use in the present process. Particularexamples of suitable microporous membranes in modified PAN membraneswith a filter surface contact angle of no more than about 25 degrees andan MWCO of 30,000 to 100,000. To be useful in commercial versions of theprocess, the membranes should be capable of maintaining substantialpermeation rates, e.g, allowing roughly 1500 to 3000 mL/min to passthrough a membrane module containing circa 12 sq. meters of membranesurface area. By employing such relatively large pore microporousmembranes, the membrane filtration operation can generally be carriedout using membrane back pressures of no more than about 100 psig. Morepreferably the membrane back pressure is no more than about 50 psig andefficient membrane separation has been achieved with back pressures inthe range of 10-20 psig.

The membrane filtration system is generally configured to run in across-flow filtration mode. Because larger particles and debris aretypically removed by the earlier clarification operation, themicroporous membrane tends not to become clogged easily. Inclusion ofthe clarification step upstream in the process tends to result in longermembrane life and higher flux rates through the membrane. The membranefiltration system typically employs one or more interchangeable membranemodules. This allows membrane pore size (or MWCO) and/or membrane typeto be altered as needed and allows easy replacement of fouled membranes.

Cross-flow filtrations can be run either continuously or in batch mode.Cross-flow membrane filtration can be run in a variety of flowconfigurations. For example, a tubular configuration, in which themembranes are arranged longitudinally in tubes similar to the tubes in ashell and tube heat exchanger, is one common configuration since itallows processing of solutions which include a variety of particlesizes. A number of other conventional cross-flow configurations, e.g.,flat sheet and spiral wound, are known to provide effective membraneseparations while reducing fouling of the membrane. Spiral woundcross-flow membrane systems are particularly suitable for use in thepresent processes, especially where the feed solution containsrelatively little particulate matter, such as a clarified oilseedextract. Spiral wound membrane modules tend to provide highly efficientseparations and permit the design of filtration systems with largemembrane surface areas in a relatively compact space.

As with the extraction operation, the temperature of theprotein-containing solution during the membrane filtration operation canaffect the chemical state of the protein (e.g., via degradation and/ordenaturation) as well as the amount of bacterial contamination whichoccurs. Lower temperatures tend to minimize chemical degradation of theprotein. However, at lower temperatures bacterial growth can be aproblem and the viscosity of more concentrated protein solutions (e.g.,solutions with at least about 10 wt. % protein) can present processingproblems. The present inventors have found that maintaining theprotein-containing extract at about 55 to 60° C. while conducting themembrane separation can effectively suppress bacterial growth whileminimizing changes in protein functionality due to chemicaldegradation/denaturation. It appears that any substantial exposure tohigher temperatures can cause changes in the protein which can makeconcentrated solutions more prone to gelling, e.g., during a subsequentspray drying operation.

When the membrane filtration is run as a batch operation, the membranesare generally cleaned in between each run. Typically the membrane systemwill have been cleaned and sanitized the day before a run and themembranes will be stored in a sodium hypochlorite solution. Before use,the membrane system the hypochlorite solution is then drained out of themembrane system and the entire system is rinsed with water. When themembrane separation is carried out as a continuous operation, themembranes are commonly shut down at periodic intervals and cleaned in asimilar fashion.

A variety of methods are known for cleaning and sanitizing microporousmembrane systems during ongoing use. One suitable cleaning procedureincludes sequentially flushing the membrane with a series of basic,acidic and sanitizing solutions. Examples of suitable sanitizingsolutions include sodium hypochlorite solutions, peroxide solutions, andsurfactant-based aqueous sanitizing solution. Typically, the membrane isrinsed with water between treatments with the various cleaningsolutions. For example, it has been found that membranes with a lowcontact angle filtering surface (e.g., modified PAN microporousmembranes) can be effectively cleaned by being flushed with thefollowing sequence of solutions:

-   -   1) Water;    -   2) Caustic solution (e.g., 0.2 wt. % NaOH solution);    -   3) Water;    -   4) Mild acid solution (e.g., aqueous solution with a pH 5.5-6);    -   5) Surfactant-based aqueous sanitizing solution (Ultra-Clean™;        available from Ecolab, St. Paul, Minn.); and    -   6) Water.

The cleaning sequence is commonly carried out using room temperaturesolutions. If the membrane is significantly fouled, it may be necessaryto carry out one or more of the rinsing steps at an elevatedtemperature, e.g., by conducting the caustic, acidic and/or sanitizingrinse at a temperature of about 40° C. to 50° C. In some instances, theeffectiveness of the cleaning sequence can be enhanced by using a morestrongly acidic rinse, e.g., by rinsing the membrane with a acidicsolution having a pH of about 4 to 5. Other types of solutions can beused as a sanitizing solution. For example, if the membrane issufficiently chemically inert, an oxidizing solution (e.g., a dilutesolution of NaOCl or a dilute hydrogen peroxide solution) can be used asa sanitizing agent. After the final water rinse in the cleaningsequence, the membrane can be used immediately to effect the membraneseparation of the present process. Alternatively, the membrane can bestored after cleaning. It is common to store the cleaned membrane incontact with a dilute bleach solution and then rinse the membrane againwith water just prior to use.

By selecting a membrane which can be effectively cleaned (e.g., amembrane with low contact angle filtering surface such as a modified PANmembrane) it is possible to carry out membrane filtration ofconcentrated oilseed protein extracts which produce retentates havingrelatively low bacterial levels. For example, by employing a modifiedPAN membrane and a cleaning procedure similar to that outlined above, itis possible to produce spray dried protein concentrates having a totalbacterial plate count of no more than about 300,000 cfu/g and,desirably, no more than about 50,000 cfu/g without subjecting theretentate to pasteurization (e.g., via HTST treatment).

Downstream Processing of Retentate

The retentate produced by the membrane filtration operation is oftenpasteurized to ensure that microbial activity is minimized. Thepasteurization generally entails raising the internal temperature of theretentate to about 75° C. or above and maintaining that temperature fora sufficient amount of time to kill most of the bacteria present in thesolution, e.g., by holding the solution at 75° C. for about 10-15minutes. The product commonly is pasteurized by subjecting theconcentrated retentate to “HTST” treatment. The HTST treatment can becarried out by pumping the concentrate retentate through a steaminjector where the protein-containing concentrate is mixed with livesteam and can be heated rapidly to about 80-85° C. (circa 80° F.). Theheated concentrate is then typically passed through a hold tube, underpressure, for a relatively short period of time, e.g., 5 to 10 seconds.After the hold tube, the heated retentate can be cooled by passage intoto a vacuum vessel. The evaporation of water from the retentate undervacuum results in flash cooling of the heated solution, allowing thetemperature to be rapidly dropped to the range of 45-50° C. (circa130-140° F.). This type of treatment has been found to be very effectiveat destroying bacteria while avoiding substantial chemical degradationof the protein.

To improve its storage properties, the modified oilseed product istypically dried such that the product contains no more than about 12 wt.% moisture, and preferably, no more than about 8 wt. % moisture, basedupon the weight of the final dried product. Depending on the dryingmethod utilized and the form of the dried product, after drying theproduct may be ground into free-flowing solid particles in order tofacilitate handling and packaging. For example, if the dried, modifiedoilseed product is dried into a cake, it can be ground into a driedpowder, preferably such that at least about 95 wt. % of the material isin the form of particles having a size of no more than about 10 mesh.

In an alternate process, after pH adjustment to a neutral pH, the liquidretentate may be spray dried to form a dry powdered product. The spraydried product is preferably dried to a water content of no more thanabout 10 wt. % water and, more preferably, about 4-6 wt. % water. Theretentate can be spray dried by passing a concentrated solution (e.g.,circa 10-15 wt. % solids) of the retentate through a spray dryer with adryer inlet temperature of about 160-165° C., a feed pump pressure ofabout 1500 psig and a discharge air temperature of about 90-95° C.

Before the heating which can occur as part of either the spray drying orHTST treatment, it is usually advantageous to adjust the pH of thesample to about neutral. For example, the pH of the retentate is oftenadjusted to between 6.5 to 7.5 and, preferably between 6.7 and 7.2 priorto any further treatment which involves heating the sample. Heating theconcentrated retentate can alter the molecular weight profile andconsequently the functionality of the product. Compare, for example, themolecular weight profile of the product of Example 2 which was not heattreated with that of the product produced according to Example 1. Theheat treated material contains a number of proteins not present itsheated treated counterpart, the product of Example 1. The DSC's of thesetwo samples also show a distinct difference. The material producedaccording to Example 2 shows a relatively sharp, symmetrical peak atabout 93° C. The other material which was not heat treated, that ofExample 4, also shows a strong absorption of energy at about 93° C. Allof the commercial products show either no absorption peak at all orsmall relatively weak absorption peak at about 82° C. DSC scans of thetwo heat treated products formed by the present method (Examples 1 and3) also only show a relatively weak absorption peak at about 82° C.

In some instances, it may be advantageous to concentrate the retentateproduced by the membrane filtration operation prior to a final spraydrying step. This can be accomplished using conventional evaporativetechniques, generally with the aid of vacuum to avoid extensive heatingof the processed soy protein material. Where a concentration step ofthis type is included in the process, it normally occurs after the pH ofthe retentate has been adjusted to a neutral pH (e.g., a pH of roughly6.8-7.0).

Characteristics of Modified Oilseed Material

The modified oilseed material can be derived from a variety of precursoroilseed materials, such as soybean meal, canola meal, sunflower meal,cottonseed meal, peanut meal, lupin meal or mixtures thereof. Soy beanflake or meal are particularly suitable sources of oilseed protein toutilize in the present method. The modified oilseed material can have avariety of characteristics that make it suitable for use as a proteinsource for incorporation into foods for human and/or animal consumption.

The modified oilseed material can be used to produce proteinsupplemented food products for human consumption. Examples of proteinsupplemented food products include beverages, processed meats, frozendesserts, confectionery products, dairy-type products, saucecompositions, and cereal grain products. The amount of modified oilseedmaterial used to supplement a food product can vary greatly depending onthe particular food product. A typical protein supplemented food productmay have between 0.1 and 10 wt. %. The modified oilseed material may beused to produce additional food products. It is also important to notethat the food products may be grouped into different or additional foodcategories. A specific food product may fall into more than one category(e.g., ice cream may be considered both a frozen dessert and adairy-type product). The food products provided herein are forillustrative purposes only and are not meant to be an exhaustive list.

Examples of protein supplemented beverage products include smoothies,infant formula, fruit juice beverages, yogurt beverages, coffeebeverages, beer, dry beverage mixes, tea fusion beverages, sportsbeverages, soy liquors, soda, slushes, and frozen beverage mixes.

Examples of protein supplemented meat products include ground chickenproducts, water-added ham products, bologna, hot dogs, franks, chickenpatties, chicken nuggets, beef patties, fish patties, surimi, bacon,luncheon meat, sandwich fillings, deli meats, meat snacks, meatballs,jerky, fajitas, bacon bits, injected meats, and bratwurst.

Examples of protein supplemented meat products include ground chickenproducts, water-added ham products, bologna, hot dogs, franks, chickenpatties, chicken nuggets, beef patties, fish patties, surimi, bacon,luncheon meat, sandwich fillings, deli meats, meat snacks, meatballs,jerky, fajitas, bacon bits, injected meats, and bratwurst.

Examples of protein supplemented confectionery products includechocolates, mousses, chocolate coatings, yogurt coatings, cocoa,frostings, candies, energy bars, and candy bars.

Examples of protein supplemented dairy-type products include yogurt,cheese, ice cream, whipped topping, coffee creamer, cream cheese, sourcream, cottage cheese, butter, mayonnaise, milk-based sauces, milk-basedsalad dressings, and cheese curds.

Examples of protein supplemented cereal grain products include breads,muffins, bagels, pastries, noodles, cookies, pancakes, waffles,biscuits, semolina, chips, tortillas, cakes, crackers, breakfastcereals, pretzels, dry bakery mixes, melba toast, breadsticks, croutons,stuffing, energy bars, doughnuts, cakes, popcorn, taco shells, frycoatings, batters, breading, crusts, brownies, pies, puffed soy cakes,crepes, croissants, flour, and polenta.

As used herein, the term “sauce compositions” refers to food productssuch as sauces, salad dressings, sandwich spreads, syrups, marinades,dips, and meat glazes. Examples of protein supplemented saucecompositions include salad dressings, nut butter spreads (e.g., peanutbutter spreads), marinades, sauces, salsas, jams, cheese sauces,mayonnaise, tartar sauce, soy humus, dips, fruit syrups, and maplesyrups.

The protein supplemented sauce composition can also include a suspendingagent to aid in maintaining the uniformity of the composition. Examplesof suitable suspending agents include polysaccharides, such as starch,cellulose (e.g., microcrystalline cellulose) and carrageenan, andpolyuronides, such as pectin. Gelatin is another example of a suspendingagent which may be used in the present beverage compositions.

Examples of other protein supplemented products include tofu, formulatedsoy essence, powdered protein supplements, juice mixable proteinsupplements, foaming agents, clouding agents, baby foods, meatlessballs, meat analogues, egg products (e.g., scrambled eggs), soups,chowders, broth, milk alternatives, soy-milk products, chili, spicemixes, sprinkles, soy whiz, salad topping, edible films, edible sticks,chewing gum, bacon bits, veggie bits, pizza crust barriers, soy pie,no-gas synthetic beans, soy helper, soy cotton candy, fruit bits, pizzarolls, mashed potatoes, spun soy protein fiber, soy roll-ups, extrudedsnacks, condiments, lotions, fries, gelatin dessert products, vitaminsupplements, and pharmaceuticals.

Consideration of the characteristics of the modified oilseed material isoften important in developing a particular protein supplemented foodproduct. For example, dispersability can facilitate easy mixing of theingredients (whether a dry formulated mix or the dry isolates) intowater, ideally leading to a relatively stable homogenous suspension.Solubility may be desired to reduce the amount of particulates that canbe found in finished beverages. Suspendability may be desired to preventthe settling of the insoluble components from the finished formula uponstanding. Generally, a white colored modified oilseed material ispreferred as tan and brown solutions can be difficult to color intowhite (milk-like) or brightly colored (fruit-like) colors. Clarity ofmodified oilseed material in solution can also be an important beveragecharacteristic. Foaming, although usually undesired in beverages as itcan complicate mixing, can also be a positive characteristic in someproducts (e.g., milk shake-like products). Other characteristics thatcan be important for particular food compositions include molecularweight, gelling capability, viscosity, emulsion stability fact contentand amino acid content. Specific properties according to one or more ofthese characteristics may be advantageous in developing proteinsupplemented food products.

The modified oilseed material formed by the present method typicallyincludes a high percentage of high molecular weight proteins and is lesscontaminated with low molecular weight proteins. A suitable method toanalyze the content of high molecular weight proteins found in thematerial is based on chromatographic data as described in Example 16.

The raw chromatogramic data may be used to calculate a number ofdifferent metrics. One metric is to calculate the molecular weight atwhich 50% of the mass is above and 50% of the mass is below. This firstmetric is not precisely the mean molecular weight, but is closer to aweighted average molecular weight. This is referred to herein by theterm “MW_(50.)” Another metric is to calculate the wt. % of modifiedoilseed material that has an apparent molecular weight that is greaterthan 300 kDa. Yet another metric is to calculate the wt. % of modifiedoilseed material that has an apparent molecular weight that is less than100 kDa. Any one of these three metrics may be used individually tocharacterize the molecular weight of a particular modified oilseedmaterial. Alternatively, combinations of two or more of these metricsmay be used to characterize the molecular weight profile of a modifiedoilseed material.

Preferably, the modified oilseed material formed by the present methodhas a MW₅₀ of at least about 200 kDa. More preferably, at least about400 kDa. Modified oilseed material that has a MW₅₀ of at least about 600kDa can be particularly suitable for some applications. As for thesecond metric mentioned above, at least about 40% of a suitable modifiedoilseed material may have an apparent molecular weight of greater than300 kDa. For some applications, it may be desirable if at least about60% of the modified oilseed material has an apparent molecular weight ofgreater than 300 kDa. According to the third metric mentioned above,preferably no more than about 40% of the modified oilseed material hasan apparent molecular weight of less than 100 kDa. For someapplications, however, preferably no more than about 35% of the modifiedoilseed material has an apparent molecular weight of less than 100 kDa.A suitable modified oilseed material may meet the preferred values ofone or more of these three metrics. For example, a particularly suitablemodified oilseed material may have a MW₅₀ of at least about 200 kDa andat least about 60% of the modified oilseed material has an apparentmolecular weight of greater than 300 kDa. Modified oilseed material thathas a MW₅₀ at least about 600 kDa and at least about 60% of the modifiedoilseed material has an apparent molecular weight of greater than 300kDa can be formed by the present method.

The modified oilseed material formed by the present method typicallyincludes a protein fraction with good solubility. For example, modifiedoilseed material where at least about 40 wt. % of the protein in a 50 mgsample of the material is soluble in 1.0 mL water at 25° C. can beformed by the present method. Samples in which at least about 50 wt. %of the protein is soluble under these conditions are attainable. Thesolubility of a modified oilseed material can also be described by itsNSI as discussed in Example 9.

In addition to having relatively good solubility, the modified oilseedmaterial formed by the present method often has good properties withrespect to its suspendability in aqueous solutions. For example, thepresent process can be used to provide modified oilseed material whichhas good suspendability. One measure of the suspendability of a driedoilseed protein product is its “turbidity factor.” As used herein, the“turbidity factor” is defined in terms of the assay described in Example14. As described in this example, sufficient sample to make a 5 wt. %solution is dissolved/dispersed in a 5 wt. % sucrose solution. Afterstanding for about 1 hour at room temperature, an aliquot of the slurryis diluted 10-fold into water and the absorbance at 500 nm was measured.This absorbance measurement at 500 nm (referred to herein as the“turbidity factor”) is a measure of turbidity with higher absorbancevalues indicating higher turbidity and lower solubility.

Preferably, the modified oilseed material formed by the present methodhas an absorbance at 500 nm of no more than about 0.95 in this assay,i.e., a turbidity factor of no more than about 0.95. Stated otherwise, adispersion of 0.5 wt. % of the dried oilseed protein product in a 0.5wt. % aqueous sucrose solution has an absorbance at 500 nm of no morethan about 0.95 (after standing for about one hour as a 5 wt. % solutionin a 5 wt. % sucrose solution).

The present method allows the production of modified oilseed materialswhich have desirable color characteristics. The products generally havea very light color as evidenced by their Gardner L values. For example,the present method allows the preparation of modified oilseed materialswhich have a dry Gardner L value of at least about 85. In someinstances, e.g., by running the extraction at a weakly alkaline pH of8-9 and conducting the initial extraction at a relatively lowtemperature (circa 25-35° C.; 75-95° F.), it may be possible to producea sample of an oilseed protein isolate which has a Gardner L value (dry)of at least about 88.

The present method further allows the production of modified oilseedmaterial which has desirable flavor characteristics. An undesirableflavor is often one of the biggest hindrances to the use of modifiedoilseed material in a consumer product. The flavor of modified oilseedmaterial, especially modified soy protein, is derived from a complexmixture of components. For example, bitterness and other off flavors areoften caused by the presence of low molecular weight peptides(400<MW<2000) and volatile compounds. Some of these small moleculesarise in the oilseed itself and others are bound to the modified oilseedmaterial at various points in the production process. The substantiallybland taste which is typical of the modified oilseed materials formed bythe present method, may be due to fewer small molecular weight peptidesand volatile compounds.

For some food related applications the ability of a modified oilseedmaterial to form a gel can be an important functional characteristic. Ingelling, the protein denatures to form a loose network of proteinsurrounding and binding a large amount of water. As used herein, theterm “gel strength” refers to the breaking strength of a 12.5 wt. %aqueous solution of the modified oilseed material after setting andequilibrating the gel at refrigerator temperature (circa 4-5° C.).Modified oilseed materials formed by the present method may have a gelstrength of no more than about 25 g.

The modified oilseed material formed by the present method typicallydemonstrate desirable viscosity properties. A modified oilseed materialthat provides a thinner solution under one set of parameters isadvantageous in applications like meat injection where thinner solutionscan more easily be injected or massaged into meat products. Typically, amodified oilseed material that does not show thinning upon heating isgenerally preferred. For some applications, it is a desirable propertyto be able to maintain viscosity through heating cycles. The modifiedoilseed material formed by the present method increases viscosity withheating so its hold on water is improving during the early stage ofcooking. In contrast, most commercial samples decrease in viscosityearly in cooking and decrease their hold on the water.

Upon heating, protein molecules vibrate more vigorously and bind morewater. At some point, the molecules lose their native conformation andbecome totally exposed to the water. This is called gelatinization instarch and denaturation in proteins. Further heating can decreaseviscosity as all interactions between molecules are disrupted. Uponcooling, both types of polymers can form networks with high viscosity(called gels). For some food related applications the ability of amodified oilseed material to form a gel can be an important functionalcharacteristic. Rapid viscosity analysis (“RVA”) was developed foranalysis of starchy samples and is generally similar to Braebenderanalysis. Given the analogy between starch and protein systems, one canapply the RVA analysis described in Example 11 to the modified oilseedmaterials formed by the present method.

According to the method described in Example 11, one can measure theslope of the viscosity line over the temperature increase from 45° C. to95° C., herein referred to as the “viscosity slope.” A suitable modifiedoilseed material may have a viscosity slope of at least about 30. Aparticularly suitable modified oilseed material may have a viscosityslope of at least about 50. As shown in Table 3, modified oilseedmaterials formed by the present method showed a viscosity slope of atleast about 70.

For some food related applications the ability of a modified oilseedmaterial to form an emulsion can be an important functionalcharacteristic. Oil and water are not miscible and in the absence of amaterial to stabilize the interface between them, the total surface areaof the interface will be minimized. This typically leads to separate oiland water phases. Proteins can stabilize these interfaces by denaturingonto the surface providing a coating to a droplet (whether of oil orwater). The protein can interact with both the oil and the water and, ineffect, insulate each from the other. Large molecular weight proteinsare believed to be more able to denature onto such a droplet surface andprovide greater stability than small proteins and thereby preventdroplet coalescence.

Emulsion stability may be determined based according to the proceduredescribed in Example 12. According to this procedure, a sample isanalyzed according to the amount of oil released from the emulsion. Asused herein, the term “Emulsion Oil Release,” or “EOR ” refers to theamount of oil released (in mL) from the emulsion according to theconditions of the assay described in Example 12. Modified oilseedprotein products prepared by the present method commonly form relativelystable emulsions. Typically, in the absence of centrifugationessentially no oil will separate from the emulsions within 2-3 hours.After the centrifugation procedure described in Example 12, a suitablematerial may have an EOR of no more than about 0.75 mL. Stated otherwiseno more than about 0.75 mL of oil may be released from the emulsion. Aparticularly suitable emulsion may have an EOR of no more than about 0.5mL and more desirably, no more than about 0.3 mL after centrifugation.

During the membrane purification operation, while the levels of somecomponents of the modified oilseed material are altered considerably,the fat content (measured after acid hydrolysis) in the present modifiedoilseed material remains relatively unchanged. Thus, if the oilseedmaterial is substantially made up of material derived from defattedsoybean flakes, the modified product obtained from the present processtypically has a fat content of about 1 to 3 wt. % (dsb). For example,processing of defatted oilseed material, such as soybean meal, by thepresent method can produce a modified oilseed product having a proteincontent of 90 wt. % (dsb) or greater with no more than about 3 wt. %(dsb) and preferably, no more than about 2 wt. % fat. As used herein,the term “fat” refers to triacylglycerols and phospholipids.

The amino acid composition of a modified oilseed material may not onlybe important from a nutritional perspective, but it may also be animportant part of determining the functional behavior of the protein.The amino acid content of a modified oilseed material may be determinedby a variety of known methods depending on the particular amino acid inquestion. For example, cysteine may be analyzed after hydrolysis withperformic acid according to known methods. To compare materials withdifferent protein contents, compositions may be recalculated to a 100%protein basis. Typically, one would expect the amino acid composition ofmaterials derived from a common starting material to be very similar.However, direct comparison of the average compositions shows that themodified oilseed materials formed by the present method includes morecysteine (assayed as cystine) than the commercial samples tested. Forexample, a suitable modified oilseed material may include at least about1.35 wt. % cysteine as a percentage of total protein. A particularlysuitable material may include at least about 1.5 wt. % cysteine as apercentage of total protein.

Cysteine can play an important role in nutrition and is one of the 10essential amino acids. Cysteine may also play a role in thestabilization of the native structure of soy proteins. Ifoxidation-reduction reagents are used to “restructure” soy proteins, thecysteines may be damaged as an unintended consequence. Loss of nativestructure might remove some of the protection of the cysteine, makingdamage to the native structure more likely. As shown in Example 18,commercial materials show a substantial loss of native structure asmeasured by molecular weight and differential scanning calorimetry.

The modified oilseed material formed by the present method can have avariety of characteristics that make it suitable for use as a proteinsource for incorporation into food products for human and/or animalconsumption. A suitable modified oilseed material may include at leastabout 85 wt. % (dsb) protein, preferably at least about 90 wt. % (dsb)protein. A suitable modified oilseed material may also have a MW₅₀ of atleast about 200 kDa and/or at least about 40% of the material has anapparent molecular weight of greater than 300 kDa. The modified oilseedmaterial may also have one or more of the following characteristics: atleast about 40 wt. % of the protein in a 50 mg sample may be soluble in1.0 mL water at 25° C.; a turbidity factor of no more than about 0.95; a13.5% aqueous solution forms a gel having a breaking strength of no morethan about 25 g; an NSI of at least about 80; at least about 1.4%cysteine as a percentage of total protein; a Gardner L value of at leastabout 85; a substantially bland taste; a viscosity slope of at leastabout 10 cP/min; an EOR of no more than about 0.75 mL; a meltingtemperature of at least about 87° C.; a latent heat of at least about 5joules/g; a ratio of sodium ions to a total amount of sodium, calciumand potassium ions of no more than 0.5; no more than about 7000 mg/kg(dsb) sodium ions; and a bacteria load of no more than about 50,000cfu/g.

A particularly desirable modified oilseed material formed by the presentmethod which may be used to produce a protein supplemented food productmay include at least about 85 wt. % (dsb) protein, preferably at leastabout 90 wt. % (dsb) protein, and meet one or more of the followingcriteria: a MW₅₀ of at least about 400 kDa; at least about 60% of thematerial has an apparent molecular weight of greater than 300 kDa; atleast about 40 wt. % of the protein in a 50 mg sample may be soluble in1.0 mL water at 25° C.; a turbidity factor of no more than about 0.95; a13.5% aqueous solution forms a gel having a breaking strength of no morethan about 25 g; an NSI of at least about 80; at least about 1.5%cysteine as a percentage of total protein; a Gardner L value of at leastabout 85; a substantially bland taste; a viscosity slope of at leastabout 50; an EOR of no more than about 0.5 mL; a melting temperature ofat least about 87° C.; a latent heat of at least about 5 joules/g; aratio of sodium ions to a total amount of sodium, calcium and potassiumions of no more than 0.5; no more than about 7000 mg/kg (dsb) sodiumions; and a bacteria load of no more than about 50,000 cfu/g.

The following examples are presented to illustrate the present inventionand to assist one of ordinary skill in making and using the same. Theexamples are not intended in any way to limit the scope of theinvention.

EXAMPLE 1

Extractions were carried out batchwise in a 50 gallon stainless steeltank. This batch size utilized 30 lbs of white flakes and 30 gallons ofwater. This allowed the extract batch to be extracted and centrifuged inno more than about 2 hours with laboratory scale equipment. The amountof bacteria growth which occurs during the extraction operation can beminimized by limiting the amount of time needed to carry out theextraction and centrifugation operations.

The extraction tank, centrifuge, centrifuge filter cloth and allutensils were sanitized with hot water and sodium hypochlorite (NaOCl)prior to use. City water (28.8 gal) at 80° F. (27° C.) was introducedinto the extraction tank. After the extraction tank agitator wasstarted, 30 lbs of soy white flakes were introduced into the extractiontank. The pH of the resulting slurry was adjusted by adding a solutionof 92 grams of sodium hydroxide dissolved in 400 mL city water. Theslurry was then stirred at room temperature for 30 minutes. The pH ofthe suspension is recorded at the beginning and end of the extractionprocess. The initial pH of the aqueous phase of the slurry was about9.0. After stirring for 30 minutes, the pH of the extract was typicallyabout 8.4 to 8.5.

A Sharples basket centrifuge was then started with the bowl set to 1800rpm. The extracted slurry was manually fed to the centrifuge at a rateof about 0.5 gpm. Clarified extract liquor was collected and transferredto the microfiltration feed tank. When the centrifuge basket was full ofspent flakes (after approximately 90 lbs of feed slurry), the cake iswashed with 4000 ml (circa 9 lbs) of city water. The centrifuge was thenstopped and the spent flakes were discarded. After rinsing thecentrifuge and washing the filter cloth, the centrifuge was restartedand the extraction sequence repeated until all of the slurry in theextraction tank had been separated. The clarified extract containedabout 4.0-5.0% soluble protein and 1.5-2.0% dissolved non-proteinmaterial and had a pH of about 7.5 to 7.8.

After about 150 lbs of extract solution was transferred from theextraction system to the membrane feed tank, the extract liquor wasrecirculated at a flow rate of about 9 gpm through a heater system whichbypassed the membranes. The water temperature of the hot water bath inthe heater system was set at 140° F. (60° C.). This is a temperaturewhich had been shown to retard bacteria growth in the clarified extract(see Example 2).

After all of the extract liquor has been transferred to the membranefeed tank, the extract liquor at 140° F. was recirculated over themembranes at 15 gpm with the membrane back pressure set at 10 psig. Themembrane filtration system contained four modified PAN membranes with anominal 50,000 MWCO (MX-50 membranes available from Osmonics,Minnetonka, Minn.) arranged in series. The total filtration surface areaof the array of membranes was about 12 sq. meters.

The membrane permeate was collected and monitored by weighing the amountof permeate collected. After being weighed, the permeate was discarded.When the amount of permeate collected equaled 67% of original totalweight of the clarified extract, the protein in the retentate had beenconcentrated by a 3× factor, from about 4% to about 12%. During theinitial concentration phase of the membrane filtration, the permeateflux typically varied from an initial rate of about 2600 ml/min to about1500 ml/min during the later stages of the concentration.

At this point the concentration operation was stopped by closing thepermeate valves and opening the back-pressure valve on the membrane. Forthe first diafiltration step, 140° F. (60° C.) water was added to theretentate in the membrane feed tank in an amount equal to the weight ofthe retentate after the concentration step. In other words, sufficientwater (“diafiltration water”) was added to lower the proteinconcentration by a factor of 2× (i.e., the volume of the retentate wasdoubled by the addition of the water). The permeate valves were thenopened and the back-pressure on the membranes was again set to 10 psig.The permeate was collected and weighed before discarding. When theweight of the diafiltration permeate was equal to the weight of thediafiltration water, the first diafiltration was complete. Thediafiltration operation was then repeated a second time. After thesecond diafiltration had been completed, the solids in the retentatenormally contained about 90 to 93% wt protein.

After the second diafiltration, the retentate from the membrane systemwas transferred to a mixing tank. The membrane system was flushed with 7gallons of city water to recover additional protein from the system.This flush water was combined with the retentate in the mixing tank.Prior to the next operation, the pH of the retentate was adjusted to 6.8to 7.0 with dilute HCl.

Following pH adjustment, the retentate was subjected to treatment at arelatively high temperature for a short time (“HTST”) in order topasteurize the retentate. The HTST step consists of pumping theconcentrate at 1 gpm to a steam injector. In the steam injector, theconcentrate is mixed with live steam and heated instantly to 280° F. Theheated concentrate passes through a hold tube, under pressure, for 5seconds. After the hold tube, the product flows in to a vacuum vesselwhere the product is flash cooled to 130° F. The product is then spraydried. The HTST step is very effective in killing bacteria, eventhermophiles. Total plate counts could be reduced from as high as300,000 cfu/g to around 100 cfu/g after the HTST operation.

The HTST treated material was then spray dried to yield a soy proteinproduct which contained circa 90-93 wt. % protein (dry solids basis) andhad a water content of about 6 wt. %. The spray dried soy proteinproduct had an average particle size of about 20 microns and had a watercontent of about 8-9 wt. %.

EXAMPLE 2

Batches (30 lbs) of soy white flakes were extracted and processedaccording to the procedure in Example 1 except that after pH adjustment(to pH 6.8-7.0) the retenate was not subjected to HTST treatment.Instead, following pH adjustment, the retenate was spray dried using theprocedure described in Example 1 to yield a soy protein product. Thespray dried soy protein product had an average particle size of about 20microns and a total bacterial count of no more than about 50,000 cfu/g.

EXAMPLE 3

Batches (30 lbs) of soy white flakes were extracted and processedaccording to the procedure described in Example 1. At the beginning ofthe extraction the pH of the resulting slurry was adjusted by adding asolution of 165 grams of sodium hydroxide dissolved in 1,000 mL citywater. The initial pH of the aqueous phase of the slurry was about 9.8and after stirring for 30 minutes, the pH of the extract was about 9.5.After pH adjustment (to pH 6.8-7.0), the retentate was subjected totreatment at a relatively high temperature for a short time (“HTST”) inorder to pasteurize the retentate using the procedure described inExample 1. The HTST treated material was then spray dried using theprocedure described in Example 1 to yield a soy protein product. Thespray dried soy protein product had an average particle size of about 20microns, contained circa 88-89 wt. % protein (dry solids basis) and hada water content of about 8-9 wt. %.

EXAMPLE 4

Batches (30 lbs) of soy white flakes were extracted and processedaccording to the procedure in Example 1 except that at the beginning ofthe extraction the pH of the resulting slurry was adjusted by adding asolution of 165 grams of sodium hydroxide dissolved in 1,000 mL citywater. The initial pH of the aqueous phase of the slurry was about 9.8and after stirring for 30 minutes, the pH of the extract was about 9.5.Following membrane filtration and pH adjustment, the retentate was spraydried to yield a soy protein product which contained circa 90 wt. %protein (dry solids basis) and had a water content of 8-9 wt. %. Thespray dried soy protein product had an average particle size of about 20microns and a total bacterial count of no more than about 50,000 cfu/g.

EXAMPLE 5

Extractions were carried out in an 80 gallon agitated stainless steeltank. One pound per minute of soy white flakes were mixed continuouslywith 2.4 gpm of city water. Caustic soda (NaOH) was added to the tank tocontrol the pH in the tank at 8.5. The temperature in the tank wascontrolled at 130° F. The average extraction retention time of 25 min.was maintained by controlling the discharge rate of the tank. Slurry waspumped continuously from the extraction tank to a decanter centrifugewhere the slurry was separated into two streams; a protein rich liquorstream and a spent flake stream.

The extraction tank, centrifuge and interconnecting piping were cleanedwith a 0.75% caustic solution and sanitized with a 500 ppm sodiumhypochlorite (NaOCl) solution prior to use.

Extract liquor was pumped to an A or B Membrane Feed Tank. The extractliquor contains about 3.0% protein. The A and B Membrane systems areused to separate the protein from the soluble carbohydrates usingultrafiltration membranes. After about 100 gallons of extract solutionwas transferred from the extraction system to the membrane feed tank,the extract liquor was recirculated at an approximate flow rate of about80 gpm through the membrane system. The temperature of the extractliquor was controlled at 140° F. (60° C.) with an in-line heatexchanger. A total of 300 gallons of extract liquor was transferred to amembrane feed tank.

After all of the extract liquor has been transferred to the membranefeed tank, the extract liquor held at 140° F. (60° C.) was recirculatedover the membranes at 80 gpm with the membrane back pressure controlledat 10-20 psig. The membrane filtration system contained six modified PANmembranes with a nominal 50,000 MWCO (MX-50 membranes available fromOsmonics, Minnetonka, Minn.). The total filtration surface area of thearray of membranes was approximately 1260 sq. feet.

During the initial concentration phase of the membrane filtration, thepermeate flux typically varied from an initial rate of about 2.5 gpm toabout 1.5 gpm during the later stages of the concentration. During thisstep the protein was concentrated from 3% to about 10%.

After the initial concentration phase, 100 gallons of 140° F. (60° C.)water was added to a Membrane Feed Tank, which dilutes the protein downto about 3.3%. The protein was then concentrated back up to 10% solids.This is called the diafiltration step. Two diafiltration steps were usedto increase the protein content of the solids, in the concentratestream, up to 90% minimum. During this run the permeate from themembrane system was discarded.

After the second diafiltration, the retentate from the membrane systemwas transferred to a dryer feed tank. The membrane system was flushedwith 30 gallons of city water to recover additional protein from thesystem. This flush water was combined with the retentate in the dryerfeed tank. Prior to the next operation, the pH of the retentate wasadjusted to 6.8 to 7.0 with dilute HCl.

Following pH adjustment, the retentate was subjected to treatment at arelatively high temperature for a short time (“HTST”) in order topasteurize the retentate. The HTST step consists of pumping theconcentrate at 2 gpm to a steam injector. In the steam injector, theconcentrate is mixed with live steam and heated instantly to 280° F.(138° C.). The heated concentrate passes through a hold tube, underpressure, for 10 seconds. After the hold tube, the product flows in to avacuum vessel where the product is flash cooled to 130° F. (54° C.). Theproduct is then spray dried. The HTST step is very effective in killingbacteria, even thermophiles. Total plate counts could be reduced from ashigh as 300,000 cfu/g to around 100 cfu/g after the HTST operation.

The HTST treated material was then spray dried to yield a soy proteinproduct having an average particle size of about 80 microns, containedcirca 90 wt. % protein (dsb) and a water content of about 8-9 wt. %.

EXAMPLE 6

Batches (240 lbs) of soy white flakes were extracted and processedaccording to the procedure in Example 5 except that after pH adjustment(to pH 6.8-7.0) the retentate was not subjected to HTST treatment.Instead, following pH adjustment, the retenate was spray dried accordingto the procedure described in Example 5 to yield a soy protein productwhich contained circa 90-93 wt. % protein (dry solids basis) and had awater content of about 6 wt. %. The spray dried soy protein product hadan average particle size of about 80 microns and a total bacterial countof no more than about 50,000 cfu/g.

EXAMPLE 7

Batches (240 lbs) of soy white flakes were extracted and processedaccording to the procedure described in Example 5 except that the pH ofthe slurry in the extraction tank was controlled at 9.5. As in Example5, following pH adjustment (to pH 6.8-7.0), the retentate was subjectedto HTST treatment in order to pasteurize the retentate. The HTST treatedmaterial was then spray dried according to the procedure in Example 5 toyield a soy protein product. The spray dried soy protein product had anaverage particle size of about 80 microns, contained circa 88-89 wt. %protein (dsb) and had a water content of about 8-9 wt. %.

EXAMPLE 8

Batches (240 lbs) of soy white flakes were extracted and processedaccording to the procedure described in Example 7 except that followingmembrane filtration and pH adjustment, the retentate was not subjectedto HTST treatment. Instead, following pH adjustment, the retenate wasspray dried to yield a soy protein product which contained circa 90 wt.% protein (dry solids basis) and had a water content of 8-9 wt. %. Thespray dried soy protein product had an average particle size of about 80microns and a total bacterial count of no more than about 50,000 cfu/g.

EXAMPLE 9 Protein Content, NSI, Solubility, F.A.H. and Color Propertiesof Modified Oilseed Material

Four soy protein isolate samples were manufactured using the proceduresdescribed in Examples 1-4 and were subjected to a number of tests tocharacterize the samples. The samples used for testing were compositesof multiple production runs in a number of cases.

The four isolate samples were manufactured by extracting soy whiteflakes at either pH 8.5 (Ex. 1 and 2) or pH 9.5 (Ex. 3 and 4). Theextracted protein was concentrated and diafiltered using a membranesystem, pH adjusted to 6.8-7.0, then either passed through a HTST system(Ex. 1 and 3) or not (Ex. 2 and 4), and finally spray dried. The samplestested were composites of multiple production runs in a number of cases.

The four prototypes were assayed for protein content (dsb), nitrogensolubility index (NSI), by the method of AOCS Ba 11-65, proteinsolubility (true solubility) and fat content (by acid hydrolysis, asis—“F.A.H.” by the method of AOAC 922.06) and the results are shown inTable 1. Results for some commercial soy protein isolate samples arealso included for comparison. PTI Supro™ 515 is a commercial soy proteinisolate recommended for use in processed meats. PTI Supro™ 760 is acommercial soy protein isolate recommended for beverage applications. Anumber of commercial samples have much higher fat contents. Whether thisis a result of processing or post-recovery addition of fat is not clear.

Protein content was analyzed using either the Kjeldahl or Lecoprocedures, or near-infrared (NIR) spectroscopy. Cysteine was analyzedusing standard methedology.

The level of free amino nitrogen (FAN) was determined using theninhydrin method (see e.g., European Brewery Convention, 1987). Solidsamples of oilseed material were extracted with water. In solution, eachsample was diluted as needed to obtain 1-3 mg/L FAN. The diluted sampleswere reacted with a buffered ninhydrin solution in a boiling water bathfor 16 min. After cooling in a 20° C. water bath for 10-20 min, thesamples were diluted using potassium iodate in a water/ethanol solution.Within 30 min of this treatment, the absorbance at 570 nm was measuredversus a control solution containing water but otherwise treated likethe samples. The FAN level was calculated from a standard line usingglycine at various concentrations as the reference.

Protein solubility was determined by weighing 50 mg samples of the soyproducts into microfuge tubes. The samples were dispersed in 1.0 mLdeionized water at room temperature and allowed to stand for one hour.After centrifuging the samples in a benchtop microfuge for 5 minutes, 50μL aliquots of supernatant were diluted with 950 μL of deionized water.The resulting solutions were diluted a second time by placing 5 μL ofthe diluted supernatant into a glass tube containing 1.0 mL deionizedwater. Bradford reagent (1.0 mL) was added to the tube and mixedimmediately. The absorbance was read at 595 nm after 5 minutes. Astandard curve based on bovine serum albumin was used to calculate theamount of protein in the original supernatants. The % solubility resultsreported in Table 6 were calculated based on an assumed proteinconcentration of 90% in the protein isolates.

TABLE 1 Protein Content, NSI, Solubility, Fat Content and Color.Protein* Solubility F.A.H. Sample (%) NSI (%) (%) Color (L) Example 190.6 85.1 54.8 1.17 89.1 Example 2 89.9 85.8 43.9 1.49 88.1 Example 388.6 33.4 13.0 1.35 86.4 Example 4 89.9 95.3 58.2 1.67 86.9 PTI Supro ™515 91.1 39.6 27.9 — 85.2 PTI Supro ™ 760 90.1 31.6 24.0 2.08 86.5 PTISupro ™ 590 — — 31.5 2.40 — PTI Supro ™ 661 91.2 — 24.8 2.07 — PTISupro ™ 710 — — 36.3 1.30 — *Protein content determined by Leco Method.

One of the most obvious differences between the prototypes, thematerials formed by the present method, and commercial samples is thecolor. The prototypes are much lighter and brighter in color than thecommercial soy isolates. This is illustrated by comparison of thereadings from a Gardner colorimeter on the samples (see Table 1). Ahigher value of “L” indicates a whiter product.

EXAMPLE 10 Gel Properties of Modified Oilseed Material

One measure of the ability of soy protein isolates to interact withwater can be seen in gelling tests. In gelling, the protein denatures toform a loose network of protein surrounding and binding a large volumeof water. A number of gelling measures can be used, but measurement ofgel strength after setting and equilibrating at refrigerator temperaturewas chosen.

The soy gel determinations were conducted according to the followingprocedure:

-   -   1. Weigh 3.5 g soy protein isolate to a 50 mL tripour plastic        beaker.    -   2. Measure out 30 mL phosphate buffer in a graduated cylinder        (0.25% NaH₂PO₄ 0.7% NaCl adjusted to pH 5.7 with NaOH).    -   3. Add approximately 10 mL of buffer to soy. Mix with a spatula        until the buffer is absorbed then add another 10 mL buffer.        Continue mixing and adding until all of the buffer is mixed in        and the mixture is homogenous. Insure that all of the soy        remains with the tripour.    -   4. Mix on high for 30 seconds with the hand held homogenizer.    -   5. Cover with aluminum foil.    -   6. Cook in 90° C. water bath for 30 minutes minimizing time        before samples are cooked to prevent settling. Cool in room temp        bath for 30 minutes. Refrigerate overnight.    -   7. Measure gel strength (deformation) by determining resistance        of the 13.5 wt. % soy isolate gel to a penetrating force using a        Texture Technologies Ti2x Texture Analyzer. The ½ inch diameter        acrylic cylinder was mounted on the instrument. The cylinder was        centered over the tripour containing the gel. The penetration        speed was set for 3 mm/sec. When a resistance of 4 g was        reached, the probe was slowed to 2 mm/second and data        acquisition was started. The probe was allowed to penetrate the        gel for 15 mm then withdrawn at 5 mm/sec.

The results of the gel tests are shown in FIG. 2. A traditional patternof gel compression involves a rising resistance, followed by a break,followed by continuing resistance. The breaking strength is one measureof gel strength. Three of the prototypes follow this pattern (see FIG.2), but one prototype (Example 2) shows no break point. Many commercialsamples of soy protein isolate also do not form gels. Some readilyseparate after cooking, some form non-breaking pastes and other formweak gels.

The weakness of the gels formed from the samples prepared according toExamples 1-4 is another major observation. The three breaking prototypesshowed break strengths around 20 g. For comparison, a series of gelatingels made at differing concentrations were run. The gelatin gel showingcomparable break strength (circa 20 g) was at 2% w/w (data not shown).Soy gels at 12-13% w/w can have break strengths of up to about 70 g,equivalent to gelatin gels between 2 and 5% w/w. In summary, the gelstrength of soy isolates is typically low and the four prototypesdescribed in Examples 4-7 are at the low end of the range expected forsoy isolates.

EXAMPLE 11 Viscosity of Modified Oilseed Material Upon Heating

Native molecules (in their natural conformation) can impart someviscosity to a suspension simply by absorbing water. Upon heating, themolecules vibrate more vigorously and bind more water. At some point,the molecules lose their native conformation and become totally exposedto the water. This is called gelatinization in starch and denaturationin proteins. Further heating can decrease viscosity as all interactionsbetween molecules are disrupted. Upon cooling, both types of polymerscan form networks with high viscosity (called gels).

RVA analysis was developed for analysis of starchy samples and isgenerally similar to Brabender analysis. For example, a sample issuspended in water with stirring. The suspension is heated under somecontrolled regime and the viscosity (resistance to stirring) isconstantly measured. The initial viscosity, peak viscosity, viscosityafter cooling and changes in viscosity during transitions (slopes) canall be diagnostic.

The viscosity determinations were conducted according to the followingprocedure:

-   -   1. Determine sample moisture content (% as is).    -   2. Weigh 2 g±0.01 g of soy isolate into a weighing vessel.    -   3. Determine water weight for 12.5% or 15% dry solids according        to manufacturer's instructions. Weigh the appropriate amount of        distilled water directly into the RVA canister.    -   4. Immediately prior to the run, pour dry sample into the        canister. Cap with a rubber stopper and vigorously shake the        mixture up and down ten times.    -   5. Wipe off residue from stopper back into the canister. Insert        a paddle into the canister, using it to scrape down any residue        off the canister walls.    -   6. Load the sample into the RVA and run the appropriate        temperature profile.

Two of the testing procedures involved the temperature and rpm profilesshown in Table 2.

TABLE 2 Temperature and rpm profiles. Elapsed Time Speed (rpm) Temp ° C.Method 1 0:00:00 960 50 0:00:10 160 50 0:04:42 160 95 0:07:12 160 950:11:00 160 50 0:13:00 160 50 Method 2 0:00:00 960 30 0:01:00 320 300:04:00 320 80 0:07:00 320 80 0:08:00 320 85 0:11:00 320 85 0:12:00 32090 0:15:00 320 90 0:16:00 320 95 0:19:00 320 95

In one experiment, performed according to the temperature and rpmprofile shown as Method 1 in Table 2, a 15% slurry of isolate in waterwas heated to 95° C., held for 2.5 minutes then cooled to 50° C. Thetypical behavior observed for the material formed by the method ofExample 2 is shown in FIG. 10. The typical behavior observed for acommercial sample of Supro™ 515 is shown in FIG. 11. Generally, theviscosity of the prototypes increased upon initial heating. Theviscosity of the commercial samples, however, decreased upon initialheating. Further, the prototypes had very low initial viscosity, whilethe commercial samples either had no viscosity at any point or had avery high initial viscosity and thinned upon heating. Within theprototypes, the samples which had not been subjected to HTST treatmentshowed viscosity development during heating. Samples that had been HTSTtreated had relatively little viscosity buildup. Each of the prototypestested formed gels upon cooling.

The potential importance of RVA analysis relates to water loss and fatretention from systems during cooking. Increased viscosity can retardthe migration of liquids. The viscosity arises from the interactionbetween the protein and the water in the system. As more water becomesbound by the protein, the viscosity of the system increases. This is oneof the most important forms of water holding and can be very persistentand stress resistant. The prototype increases viscosity with heating soits hold on water is improving during the early stage of cooking. Incontrast, most commercial samples decreased in viscosity early incooking and decreased their hold on the water. “Free” water would tendto be more available to evaporate or drain from the product.Additionally, other potentially fluid components of the system (likefat) would be less likely to drain from a system due to the increasedresistance provided by a higher viscosity.

The data from another experiment, performed according to the temperatureand rpm profile shown as Method 2 in Table 2, allows one to measure thechange in viscosity (in centipoise, “cP”). As used herein, the viscosityslope is calculated by determining the difference between an initialviscosity at 43° C. and a final viscosity at 95° C. and dividing thedifference by the time. The viscosity slope is computed from the initialviscosity (at 43° C.) and the final viscosity (95° C.) without regard toviscosities at any point in between. Results of this analysis are shownin Table 3 for 12.5% slurries of modified oilseed material. As theresults indicate, only one of the commercial samples have a positiveviscosity slope (in cP/min).

TABLE 3 Viscosity Slope and Initial Viscosity. Material Viscosity Slope(cP/min) Viscosity at 1 Min (cP) Example 1 3.87 478 Example 2 53.97 296Example 3 −25.70 1502 Example 4 74.33 442 Example 5 7.83 120 Example 677.27 56 Example 7 12.13 151 Example 8 77.23 127 Supro ™ 610 0.20 —Supro ™ 515 −7.30 579 Profam ™ 891 −13.23 391 Supro ™ 760 −23.43 633Profam ™ 982 −25.43 541

Another measure that can be made is of the “initial viscosity” (theviscosity after 1 min. of mixing at about 30° C.). This comparison isalso reported in Table 3. The material formed by the method described inExample 3 had an exceptionally high initial viscosity (about 1500 cP),but generally the examples had lower initial viscosities than thecommercial samples. The combination of low initial viscosity and anincrease in viscosity upon heating may be an advantage in applicationslike processed meat products where thinner solutions can more easily beinjected or massaged into meat products but can be less likely to loosewater during cooking.

EXAMPLE 12 Emulsion Stability of Modified Soy Material

One of the potential functional properties of proteins is stabilizationof interfaces, for example the oil-water interface. Oil and water arenot miscible and in the absence of a material to stabilize the interfacebetween them, the total surface area of the interface will be minimized.This typically leads to separate oil and water phases. It is widelybelieved that proteins can stabilize these interfaces.

An analysis was performed according to the following procedure. Samplesof 10 mg were suspended in 13 mL of 50 mM sodium phosphate at pH 7.0.After 15-20 minutes of hydration, 7 mL of corn oil was added. Themixture was homogenized for 1 minute at high speed with a handheldpolytron-type homogenizer. A pipette was used to transfer 12 mL of theemulsion phase (avoiding the aqueous phase forming) to a graduatedcentrifuge tube. The tubes were centrifuged in a clinical centrifuge atfull speed for 30 minutes. The volume of oil released duringcentrifugation was recorded. Oil volume was read from the bottom of themeniscus to the top of the aqueous layer (which was typically flat). Inthe absence of centrifugation, no oil separates from the emulsionswithin 2-3 hours. No measurement of the aqueous layer or emulsion layerwas made.

The results shown in Table 4 suggest that the prototypes are capable ofstabilizing emulsions much better than the commercial products tested.As used herein, the term “Emulsion Oil Release,” or “EOR” refers to theamount of oil (in mL) released from the emulsion according to the assaydescribed above.

TABLE 4 Emulsion oil released after centrifugation. Sample Producer EOR(mL) Example 6 Cargill 0.20 Example 5 Cargill 0.25 Example 7 Cargill0.25 Example 8 Cargill 0.25 Example 1 Cargill 0.35 Example 4 Cargill0.40 Supro XT10 PTI 0.45 Profam 891 ADM 0.45 Example 2 Cargill 0.50Example 3 Cargill 0.55 FX950 PTI 0.60 Supro ™ 670 PTI 0.65 Supro ™ 710PTI 0.65 FP 940 PTI 1.15 Supro ™ 425 PTI 1.45 Profam ™ 981 ADM 1.65Profam ™ 974 ADM 1.93 Supro ™ 661 PTI 2.75 Supro ™ 515 PTI 2.77 Supro ™590 PTI 2.90 Supro ™ 760 PTI 3.10 Supro ™ 500E PTI 3.40 Profam ™ 648 ADM3.45

The hypothesis that high molecular weight proteins would be morefunctional under stress was tested by calculating the correlationcoefficients between the emulsion oil released and the molecular weightvalues reported in Table 11. As the results show, oil release wasnegatively correlated with the portion of protein greater than 300 kDAand the weighted average molecular weight MW₅₀. In other words, largeproteins tended to hold the oil better.

TABLE 5 Correlation coefficients between molecular weight measures andEOR. EOR Greater than 300 kDa Pearson Correlation −.655 Sig. (2-tailed).001 Less than 100 kDa Pearson Correlation .554 Sig. (2-tailed) .007MW₅₀ Pearson Correlation −.493 Sig. (2-tailed) .020

EXAMPLE 13 Flavor Attributes of Modified Oilseed Material

Beverage products generally place some different demands on the physicalproperties of protein isolates. Flavor is a much more importantattribute because the protein isolate can be a much larger portion ofthe finished product. This is especially the case with beveragesintended to meet the health claim criteria. Some fortified adultbeverages contain small amounts of isolate with the bulk of the proteinderived from milk products. In order to successfully compete with suchproducts, beverages based on vegetable protein isolates must havecomparable flavor qualities.

A flavor panel conducted tests on 5% dispersions of the protein isolatesin water. The materials from Examples 1-4 were compared to PTI Supro™760, an isolate commonly used in beverages. Preparation of the testsolutions allowed a number of observations to be made. The prototypesdid not disperse well, compared to the Supro™ 760 and had to be mixed inwith a Waring blender. Consequently, about 4-times as much foaming wasobserved with the prototypes. The resulting solutions also had adifferent “color” than the commercial product, essentially appearing tobe darker. The Example 4 product was the darkest.

Some of the flavor attributes identified by the flavor panel are shownin Table 6. With the exception of the Example 3 product, the prototypeswere associated more with grainy flavors than the commercial product.This could be a significant advantage in formulating beverages.

The same five isolates were then formulated into an adult beveragesimilar to one sold ready-to-eat in cans. The product formula onlyincluded soy protein product at 0.7% of the formula (as is). The totalformula is about 30% solids, 12% protein (dry basis) and about 18% ofthe protein present is from the soy isolate. The overall contribution ofsoy protein to the formula is about 0.6%. Not surprisingly, there wereno observable differences in flavor between the finished products.

TABLE 6 Flavor Attributes Total Intensity of Sample Flavor Flavor NotesSupro ™ 760 1 Cardboard, starchy, starchy mouth- feel, sour Example 11.5 Sweet grain, oat-like, sour, wall- paper paste Example 2 1-1.5Boiled rice, sweet, starchy, starchy mouthfeel Example 3 1-1.5 Wet wool,starchy, starchy mouth- feel, slightly earthy Example 4 0.5 Grainy,grassy-green, dimethyl- sulfide (like cream corn), rice water

EXAMPLE 14 Solubility Attributes of Modified Oilseed Material

Slurries (5% (w/w)) were made up in the presence of 5% (w/w) sucrose indeionized water. The four prototypes were somewhat difficult to wet andhad to be mixed with a homogenizer to get uniform slurries. This was notrequired for the two commercial products. The resulting slurries wereallowed to stand for about 1 hour at room temperature, then aliquotswere diluted 10-fold into water and the absorbance at 500 nm wasmeasured. This absorbance measurement is influenced by turbidity and/orsolubility; higher absorbance values indicated lower solubility. Theresults are shown in Table 7. The observations suggest that three of theprototypes were more prone to go into solution than to simply besuspended in the slurry. This could be an advantage in formulatingbeverage products where opacity is not desired. Photos were also takenof the slurries immediately after settling for 16 hours (FIG. 4) andafter subsequent remixing (FIG. 3). The three prototypes that showed thelowest absorbance in Table 7 also showed the least settling overnight.While it may not be apparent from the photos, the slurry derived fromthe Example 3 prototype had a distinctly brownish tint. It was clearfrom further observation that a lack of particulates tended to make thesuspensions look darker. Upon settling, the upper portion of theslurries made with the commercial samples darkened. Shaking the slurriesmade them appear lighter again.

TABLE 7 Absorbance of Protein Isolate Slurries in Sucrose Solutions.Sample Absorbance (500 nm) Example 2 0.894 Example 1 0.856 Example 40.581 Example 3 1.294 Supro ™ 760 1.078 Supro ™ 670 1.531

Samples of the prototypes were also formulated into an adult beverage. Ahigh-soy protein beverage that would meet the new health claimrequirements was targeted. The initial formulas were quite simple (seeTable 8). Beverages formulated from the prototypes were compared to onesbased on Supro™ 670 (from Protein Technology Inc.) and Profam™ 974 (fromArcher Daniels Midland). These were the products recommended by therespective manufacturers for formulation of beverages of this type.

TABLE 8 Formulas for Flavored high-soy beverage mixes. IngredientVanilla-flavored Chocolate-flavored Soy isolate 38.20 32.21 Sugar 57.2948.32 Cocoa — 15.66 Vanilla powder 2.65 2.24 Salt 1.86 1.57 TOTAL 100.00100.00

Sensory evaluation was performed on the prototype beverages and oncomparable beverages made with the commercial products. Dry mix ofchocolate (44.7 g) or vanilla (37.7) were added to 472 g water, mixed ina Waring blender for about 10 seconds to completely mix and evaluated ona scale from one (poor) to five (good). These levels of additionresulted in identical soy protein contents in the finished beverage(6.48 g per 8-ounce serving). Overall ratings of soy-based beveragescontaining prototype and commercial isolates are shown in Table 9. Theratings are the average of scores from 7 panelists. It was noted thatthe flavored beverages based on the prototypes of Examples 1-4 lackedany gritty mouthfeel and that settled less upon standing than thecommercial products.

TABLE 9 Flavor Ratings of soy-based beverages. Material Vanilla-flavoredChocolate-flavored Example 1 3.01 3.43 Example 2 2.09 3.08 Example 32.54 2.26 Example 4 3.03 3.54 Profam ™ 974 2.19 2.64 Supro ™ 670 2.032.41

EXAMPLE 15 Protein, Fat, Fiber, Moisture, Ash and Fiber Content ofModified Oilseed Material

Additional analyses of the compositions of the four prototypes describedin Examples 1-4 were analyzed for protein, fat, fiber, moisture, and ashcontent. The results are shown in Table 10. The analyses were conductedusing standard AOAC methods. Crude fiber followed method AOAC 962.09.Fat (by acid hydrolysis) followed method AOAC 922.06. Moisture and ashfollowed method AOAC 930.42/942.05. Protein (Kjeldahl using a 6.25conversion factor) was conducted using method AOAC991.20.1.

One of the consequences of protein degradation by enzymes (or acid) isthe release of alpha-amines. These amines react with ninhydrin and allowa way to measure the degree of hydrolysis. This method was applied tothe commercial and prototype isolates with the results shown in Table10. Though large differences between commercial isolates are evident,there is no systematic difference between the samples of Examples 1-4and the commercial samples. Examples of soy protein products with high,medium or low concentrations of FAN were found.

TABLE 10 Example 1 Example 2 Example 3 Example 4 Protein* 83.06 81.4079.69 81.17 FAN (mg/g) 0.57 1.09 0.40 2.06 Fat** 2.14 1.48 1.24 1.17Moisture 5.86 8.45 8.09 8.45 Ash 5.65 5.97 6.51 6.18 Fiber 0.15 0.120.27 0.17 *Protein content determined by Kjeldahl Method. **Fat contentdetermined by acid hydrolysis

EXAMPLE 16 Molecular Weight Profiles of Modified Oilseed Material

One indicator of the amount of proteins still present in their nativestructure is their molecular weight profile. For pure proteins,chromatography usually reveals a single symmetric peak. Mixtures ofproteins, as would exist in soy isolate, should generally consist of aseries of symmetric peaks. This is illustrated in FIG. 5, which is achromatogram showing the molecular weight profile of an extract fromuntoasted, defatted soy flakes. If processing did not result in breakingup of the protein, a similar profile would be expected to be observedfor soy isolates.

Samples of soy protein products (25 mg) were suspended in 1 mL of 50 mMsodium phosphate-NaOH (pH 6.8). The samples were mixed vigorously (andoccasionally sonicated) for a total of 20 minutes. The samples werecentrifuged for 1 minute in a microfuge to settle the insolubles.Supernatant (100 μL) was dilated with solvent (900 μL), filtered througha 0.45 μm syringe filter and 100 μL of the filtered sample was injectedonto the HPLC. The HPLC columns were a tandem set comprising Biorad SEC125 and SEC 250 gel chromatography columns equilibrated with 50 mMsodium phosphate-NaOH (pH 6.8), 0.01% w/v sodium azide. Flow rate wasset at 0.5 mL/min and the elution of proteins was monitored at 280 nm.In addition to the samples of the soy protein products, a sample offresh, clarified extract (pH 8.5) of soy flakes was diluted inequilibration buffer and run to provide an untreated comparison. Inbrief, the vast majority of commercial samples (not shown) show signs ofdegradation, sometimes significant amounts of degradation. The prototypesamples of Examples 1-8, however, showed substantially less evidence ofdegradation.

Degradation could be accidental or deliberate. Accidental degradationcould arise from mechanical damage (e.g., high shear or cavitationmixing), acid or alkali hydrolysis during heating steps, or enzymatichydrolysis at any time during processing. The enzymatic hydrolysis couldbe due to either protein degrading enzymes naturally present in the soyor enzymes secreted by contaminating bacteria. The proteins could alsobe intentionally degraded in order to improve the functional propertiesof the protein. Partial hydrolysis can improve emulsification or foamingproperties of soy proteins. Extensive hydrolysis can improve solubilityunder acidic conditions.

Samples of commercial soy isolates were obtained from various commercialsources. The collection of the raw molecular weight profile data isdescribed above. An analysis of this raw chromatographic data that usesthe correlation between elution time and molecular weight was used. TheHPLC gel filtration column was calibrated with a set of proteins of“known” molecular weight. A calibration curve was generated and theequation for that calibration determined. The chromatographs for thesamples were then sliced into 30-50 sections and the areas for thoseslices calculated. This was converted into “area percent” by dividingthe slice's area by the total area for the chromatogram (limited to themolecular weight range between about 1000 daltons and the breakthroughmolecular weight). The elution times for each slice were plugged intothe calibration formula and the corresponding molecular weights werecalculated. A plot was then generated comparing the cumulativepercentage of protein detected and the molecular weight. One example ofthe potential comparison is shown in FIG. 8.

The analysis is analogous to that used for particle size analysis inemulsions. For example, one can ask what percentage of the material isless than 100 kDa. For Supro™ 425, the less than 100 kDa fractioncomprises about 62%, while for the material formed by the methoddescribed in Example 6, this fraction comprises about 30%. Another wayto analyze the chromatographic data is to calculate the molecular weightat which 50% of the mass is above and 50% of the mass is below. This isnot precisely the mean molecular weight, but is closer to a weightedaverage molecular weight. This is referred to herein by the term “MW₅₀.”The MW₅₀ for Supro™ 425 is about 50 kDa, while the MW₅₀ for the materialformed by the method of Example 6 material is about 480 kDa.

TABLE 11 Molecular Weight Metrics. Product Wt. % >300 Wt. % <100 MW₅₀(kDa) Example 8 73 14 600 Example 5 72 39 520 Example 7 67 23 680Example 6 64 28 480 Example 4 47 33 290 Example 2 44 50 100 Extract 3060 40 Example 1 30 60 40 Example 3 27 59 80 FX940 22.5 59 55 Profam ™891 20 50 100 Profam ™ 974 20 66 39 Supro ™ 670 20 62 55 Supro ™ 515 1865 60 Supro ™ 500E 16 60 68 FXP ™ 950 15 70 6 Supro ™ 610 15 60 85Supro ™ 590 14 54 85 Supro ™ 425 10 65 50 Supro ™ 710 9 76 29 Supro ™760 7 67 55 Supro ™ 661 6 64 70 Profam ™ 981 5 81 28 Profam ™ 648 4 8411 Profam ™ 982 2.5 87 25

The present prototypes (the materials formed by the methods described inExamples 1-8) have a significantly higher percentage of high molecularweight proteins than the commercial samples. Most commercial samplesexamined had significantly less high molecular weight material than theraw extract

The possible impacts of higher molecular weight fractions could come ina number of areas. One benefit is the reduced presence of bitterpeptides. Hydrolysis of proteins to low molecular weight peptides(400<MW<2000) often results in production of compounds with bitterflavor. One example of this is aspartame, which is associatedexceptional sweetness but also with a bitter aftertaste. The flavor ofsoy protein is derived from a complex mixture of components. Bitternessis one of these off-flavors. The reduced peptide content couldcontribute to a less bitter tasting product.

A second consequence of high molecular weight could be in interfacestabilization. Though air-water and oil-water interfaces may be betterstabilized initially by lower molecular weight materials, stabilizationof these surfaces may depend on larger molecules. It is worth notingthat some of the best emulsion stabilization results were observed arewith the materials made by the methods described in Examples 5-8.

EXAMPLE 17

DSC Scans of Modified Oilseed Material

Samples of soy protein products (50 mg) were weighed into a sample vial,mixed with 50 μL water and crimped shut. Samples were placed in aPerkin-Elmer DSC and heated at 10° C./min from about 30° C. to about135° C.

Calorimetry scans of the modified oilseed materials formed by themethods described in Examples 1-4, see, e.g., FIGS. 7 and 8, were made.In brief, native soy protein (as represented by a spray dried sample ofa crude extract obtained from untoasted, defatted soy flakes) has amaximum energy absorption at about 93° C. with a side peak of absorptionaround 82° C. The 93° C. peak apparently represents the 11S protein andthe 82° C. peak the 7S protein (see, e.g., Sorgentini et al., J. Ag.Food Chem., 43:2471-2479 (1995)). The data obtained from DSC scans ofthe protein products of Examples 1-4 as well as for Supro™ 670 aresummarized in Table 12. The soy protein products from Examples 2 and 4showed large peak energy absorption at about 93° C. (see, e.g., FIG. 7).The soy protein products from Examples 1 and 3 showed smaller peakenergy absorption at about 82° C. (see, e.g., FIG. 8). Commercialsamples tended to show peaks only around 82° C. and a number ofcommercial samples show no signs of heat absorption at all, indicatingthat the protein in the sample was already completely denatured. Nocommercial samples showed a peak at 93° C.

TABLE 12 DSC Analysis of Soy Protein Isolates Supro ™ Ex. 1 Ex. 2 Ex. 3Ex. 4 670 Peak Energy 82.68° C. 94.28° C. 82.5° C. 92.21° C. 82.53° C.Absorption Energy of  0.98  9.24  1.39  8.30  1.37 Absorption (J/g)

EXAMPLE 18

Amino Acid Content of Modified Oilseed Material

The amino acid composition of a modified oilseed material may not onlybe important from a nutritional perspective, but is an important part ofdetermining the functional behavior of the protein. The amino acidcontent of a modified oilseed material may be determined by a variety ofknown methods depending on the particular amino acid in question. Forexample, cysteine may be analyzed after hydrolysis with perfomic acidaccording to known methods. To compare materials with different proteincontents, compositions may be recalculated to a 100% protein basis.Typically, the amino acid composition materials derived from a commonstarting material would be expected to be very similar. Table 13 showsthe amount of cysteine as a weight percent of the total amount ofprotein in a number of soy protein isolates. As shown in Table 13,direct comparison of the average compositions shows that cysteine(assayed as cystine) in the materials formed by the present methodinclude about 17% more cysteine that the commercial sample average.

TABLE 13 Cysteine Content Product Cys Example 5 1.56% Example 6 1.46%Example 7 1.46% Example 8 1.42% Supro ™ 760 1.26% Supro ™ 515 1.24%Profam ™ 982 1.28% Profam ™ 891 1.28% Prototype Average 1.48% CommercialAverage 1.27% Ratio - Prototype/Commercial 1.116

EXAMPLE 19

Conductivity/Salt Content of Modified Oilseed Material

Suspension (5% (w/v)-dsb) of samples of soy protein products wereprepared in distilled deionized water. Each suspension was vigorouslymixed without pH adjustment and left standing for 20-60 min at RT. Thesuspension was re-mixed and the conductivity measured. The pH wasadjusted to 7.0 and the conductivity measured again.

Analyses for sodium, calcium and potassium content of samples werecarried out using a modification of the EPA 6010B method. In brief,samples were refluxed in nitric acid, cooled, filtered and diluted byinductively coupled plasma spectroscopy-atomic emission spectroscopy.Two samples were analyzed in duplicate, spikes with standard sampleswere used to confirm complete recovery of ions and two samples withexceptionally high sodium contents were reconfirmed by additionalanalysis. All checks indicated that the results were reliable.

The modified oilseed materials formed by the present method generallyhave a relatively low amount of sodium ions. This is reflected in a lowratio of sodium ions as a percentage (on a weight basis) of the total ofsodium, calcium and potassium ions. Typically, the ratio of sodium ionsto the total of sodium, calcium and potassium ions is no more than about0.5:1.0 (i.e., 50%) and, more desirably, no more than about 03:1.0(i.e., 30%). In some instances, it may be possible to produce modifiedsoy protein materials where the ratio of sodium ions to the total ofsodium, calcium and potassium ions is no more than about 0.2:1.0 (i.e.,20%). The method allows the production of modified soy protein materialswith levels of sodium ions of no more than about 7000 mg/kg (dsb). Byemploying deionized water in the extraction and/or diafiltration steps,it may possible to produce modified soy protein materials with evenlower levels of sodium ions, e.g., sodium ion levels of 5000 mg/kg (dsb)or below.

Soybeans contain relatively little sodium, but substantial quantities ofpotassium and calcium. A number of bases may be used in the processingof soy isolates that could end up as part of the finished product. Whilesodium hydroxide would be the most common choice, calcium and potassiumhydroxides could also be employed. For example, calcium hydroxide mightbe used to attempt to produce a soy isolate more similar to milkprotein. Because the process described in Examples 1-4 to manufacturethe soy protein products has few pH changes and the final pH change isdownward, there was a reasonable chance that lower levels of sodiumwould be found, compared to products produced by commercial processes.This is confirmed by the results of the analysis, shown in Table 14.

The material produced in Examples 1-4 have significantly lower sodiumcontent and significantly higher potassium content than the samples ofcommercial soy isolates. With two exceptions, the calcium content of thesamples from Examples 1-4 was much higher than the commercial samples.Most surprising is the extremely low potassium and calcium contents ofseveral products (exemplified by Profam™ 974).

TABLE 14 Supro ™ Profam ™ Ex. 1 Ex. 2 Ex. 3 Ex. 4 760 974 Conduc- tivity(Mi- cromhos) As is pH 1350 1850 2200 1850 1000 1200 pH 7 1810 1850 40502020 2850 1600 Cation Content (mg/kg) Na 4200 6700 5600 5700 12000 13000Ca 4800 5000 5400 4500 3900 390 K 14000 12000 14000 14000 1600 930Na/(Na + 18.3 28.3 22.4 23.6 68.6 90.8 Ca + K)

EXAMPLE 20

Yogurt Supplemented with Modified Oilseed Material

A soy yogurt that meets the soy protein health claim requirements (i.e.,6.25 grams soy protein per serving (180 grams) and provides 30% RDI ofcalcium) was prepared from a yogurt base and a flavor base. The yogurtbase was prepared from the following ingredients:

Ingredients Parts % Water 27  Milk (0% fat) 63  Sugar 5 Soy proteinisolate (Example 5) 4 Germantown Starch/gelatin blend (Crown) 1 Theflavor base was prepared from the following ingredient: Liquid sucrose(67%) 13.38  55 High Fructose Corn Syrup 7.14 Water 0.50 Robertet, PeachFlavor 15,358 0.21 Robertet, Peach Flavor 17,580 0.10 Red food color 0.012 Yellow food color  0.024 Calcium citrate (fine grade) 0.63   22Peach Jam 0.98

The soy protein isolate was hydrated in water preheated to 145° F. (63°C.), using a handheld homogenizer and further dispersed in a blender.The stabilizer system (starch/gelatin blend) and the sugar werepre-blended and added slowly to the soy protein dispersion while mixing.The mix was batch-pasteurized to 185° F. (85° C.) and held at thistemperature for 10 minutes. The loss of water during pasteurization wascompensated by water addition after the holding time. The mix wasinoculated with live culture bacteria (0.5% of the batch weight of amixture of Lactobacillus bulgaricus, Streptococcus Thermophilus,Lactobacillus Acidophilus and Bifidus), incubated at 102° F. (40° C.)and cooled. The yogurt base was dispensed into jars and incubated untilpH 4.6 was reached (approximately 5 hours).

A flavor base fortified with calcium was then prepared according to thefollowing method and added to the yogurt base. 0.8% (based on the finalweight of the yogurt used) calcium citrate was weighed. An amount offlavoring at a ratio of 82:18 (100 parts yogurt base per 22 partsflavor/color) was weighed. The calcium citrate was added to thepre-weighed flavoring and mixed with a handheld homogenizer. The calciumcitrate and flavoring mixture was added to the yogurt base and mixed.The mixture was homogenized with a Virtis high-shear mixer for about 2min. at 10,000 RPM. The peach jam was weighed and blended into thehomogenized yogurt. The resulting mixture was then packaged incontainers and refrigerated.

EXAMPLE 21 Pizza Sauce Supplemented with Modified Oilseed Material

A tomato based pizza sauce was developed that could be used to reducethe amount of meat toppings required to meet CN standards for schoollunch pizzas. Each ¼ cup (60 ml) Recommended Amount Customarily Consumed(RACC) serving contains 1 gram soy protein. The pizza sauce was preparedfrom the following ingredients:

Ingredients Formula Tomato Paste (28 brix) 39.85 Water 54.31 ModifiedFood Starch 1.01 Sucrose 0.50 Salt 1.01 Paprika .26 Oregano .41 BlackPepper .28 Maltodextrin .50 Soy Isolate (Example 5) 1.87

The soy isolate and water were combined and homogenized with a handheldhomogenizer for two minutes on high speed. The tomato paste was addedand the resulting mixture was mixed until blended. The remaining dryingredients were combined and added to the tomato paste mixture andblended until combined.

Additional Illustrative Embodiments

A description of a number of additional illustrative embodiments isprovided below. The embodiments described are intended to illustrate thepresent materials and methods and are not intended to limit their scope.

A modified oilseed material may be formed that has at least about 85 wt.% (dsb) protein and an MW₅₀ of at least about 200 kDa. Moreover, atleast about 40 wt. % of the protein in a 50 mg sample of the modifiedoilseed material may be soluble in 1.0 mL water at 25° C. The modifiedoilseed material may further meet one or more additional criteria.

For example, a dispersion of 0.5 wt. % (dsb) of the modified oilseedmaterial in a 0.5 wt. % of aqueous sucrose solution that has anabsorbance of no more than about 0.95 at 500 nm may be formed. Themodified oilseed material may also have an EOR of no more than about0.75 mL. Additionally, a 13.5% aqueous solution of the modified oilseedmaterial may form a gel having a breaking strength of no more than about25 g.

Another example is that the modified oilseed material may have aviscosity slope of at least about 20 cP/min. The modified oilseedmaterial may also have a melting temperature of at least about 87° C.Additionally, at least about 40% of the modified oilseed material mayhave an apparent molecular weight of greater than 300 kDa.

An additional example of a useful criterion is that the modified oilseedmaterial may also have a turbidity factor of no more than about 0.95.The modified oilseed material may also have a dry Gardner L value of atleast about 85. Additionally, the modified oilseed material may have anNSI of at least about 80.

Another example is that the modified oilseed material may include atleast about 1.4 wt. % cysteine as a percentage of total protein. Themodified oilseed material may also have a latent heat of at least about5 joules/g. Additionally, the modified oilseed material may have a ratioof sodium ions to a total amount of sodium, calcium and potassium ionsof no more than about 0.5.

An additional example is that the modified oilseed material may have nomore than about 7000 mg/kg (dsb) sodium ions. The modified oilseedmaterial may also have a substantially bland taste. Additionally, themodified oilseed material may include modified soybean material.

The modified oilseed material may be included in a food product at about0.5 to 5 wt. % (dsb). The modified oilseed material may also comprisesat least about 90 wt. % (dsb) protein. Additionally, the modifiedoilseed material may have a bacteria load of no more than about 50,000cfu/g.

A modified oilseed material may be formed that can have at least about85 wt. % (dsb) protein and at least about 40% of the modified oilseedmaterial can have an apparent molecular weight of greater than 300 kDa.Moreover, at least about 40 wt. % of the protein in a 50 mg sample ofthe modified oilseed material may be soluble in 1.0 mL water at 25° C.The modified oilseed material may further meet one or more additionalcriteria.

For example, a dispersion of 0.5 wt. % (dsb) of the modified oilseedmaterial in a 0.5 wt. % of aqueous sucrose solution that has anabsorbance of no more than about 0.95 at 500 nm may be formed. Themodified oilseed material may also have an EOR of no more than about0.75 mL. Additionally, a 13.5% aqueous solution of the modified oilseedmaterial may form a gel having a breaking strength of no more than about25 g.

Another example is that the modified oilseed material may have aviscosity slope of at least about 20 cP/min. The modified oilseedmaterial may also have a melting temperature of at least about 87° C.Additionally, the modified oilseed material may have an MW₅₀ of at leastabout 200 kDa.

An additional example is that the modified oilseed material may have aturbidity factor of no more than about 0.95. The modified oilseedmaterial may also have a dry Gardner L value of at least about 85.Additionally, the modified oilseed material may have an NSI of at leastabout 80.

Another example is that the modified oilseed material may include atleast about 1.4 wt. % cysteine as a percentage of total protein. Themodified oilseed material may also have a latent heat of at least about5 joules/g. Additionally, the modified oilseed material may have a ratioof sodium ions to a total amount of sodium, calcium and potassium ionsof no more than about 0.5.

An additional example is that the modified oilseed material may have nomore than about 7000 mg/kg (dsb) sodium ions. The modified oilseedmaterial may also have a substantially bland taste. Additionally, themodified oilseed material may include modified soybean material.

The modified oilseed material may be included in a food product at about0.1 to 10 wt. %. The modified oilseed material may also comprises atleast about 90 wt. % (dsb) protein. Additionally, the modified oilseedmaterial may have a bacteria load of no more than about 50,000 cfu/g.

A modified oilseed material may be formed having at least about 85 wt. %(dsb) protein and at least about 40% of the modified oilseed materialcan have an apparent molecular weight of greater than 300 kDa. Themodified oilseed material may further have an MW₅₀ of at least about 200kDa and a viscosity slope of at least about 20 cP/min. The modifiedoilseed material may include at least about 90 wt. % (dsb) protein.Moreover, the modified oilseed material may comprise modified soybeanmaterial.

A modified oilseed material may be formed having at least about 85 wt. %(dsb) protein and at least about 40% of the modified oilseed materialcan have an apparent molecular weight of greater than 300 kDa. Themodified oilseed material may further have an MW₅₀ of at least about 200kDa and at least about 40 wt. % of the protein in a 50 mg sample of themodified oilseed material may be soluble in 1.0 mL water at 25° C. Themodified oilseed material may include at least about 90 wt. % (dsb)protein. Moreover, the modified oilseed material may comprise modifiedsoybean material.

A modified soybean material may be formed having at least about 85 wt. %(dsb) protein and at least about 40% of the modified oilseed materialcan have an apparent molecular weight of greater than 300 kDa. Themodified oilseed material may further have an MW₅₀ of at least about 200kDa and a dispersion of 0.5 wt. % (dsb) of the modified oilseed materialin a 0.5 wt. % of aqueous sucrose solution may have an absorbance of nomore than about 0.95 at 500 nm. The modified oilseed material mayinclude at least about 90 wt. % (dsb) protein. Moreover, the modifiedoilseed material may comprise modified soybean material.

A modified oilseed material may be formed having at least about 85 wt. %(dsb) protein and at least about 40% of the modified oilseed materialcan have an apparent molecular weight of greater than 300 kDa. Themodified oilseed material may further have an MW₅₀ of at least about 200kDa and a melting temperature of at least about 87° C. The modifiedoilseed material may include at least about 90 wt. % (dsb) protein.Moreover, the modified oilseed material may comprise modified soybeanmaterial.

A modified oilseed material may be formed having at least about 90 wt. %(dsb) protein and at least about 40% of the modified oilseed materialcan have an apparent molecular weight of greater than 300 kDa. Themodified oilseed material may further have an MW₅₀ of at least about 200kDa and an EOR of no more than about 0.75 mL. The modified oilseedmaterial may include at least about 90 wt. % (dsb) protein. Moreover,the modified oilseed material may comprise modified soybean material.

A modified oilseed material may be formed having at least about 90 wt. %(dsb) protein and at least about 40% of the modified oilseed materialcan have an apparent molecular weight of greater than 300 kDa. Themodified oilseed material may further have an MW₅₀ of at least about 200kDa and a turbidity factor of no more than about 0.95. The modifiedoilseed material may include at least about 90 wt. % (dsb) protein.Moreover, the modified oilseed material may comprise modified soybeanmaterial.

A modified oilseed material may be formed by a process which includesextracting oilseed material with an aqueous alkaline solution to form asuspension of particulate matter in an oilseed extract and passing theextract through a filtration system including a microporous membrane toproduce a permeate and a protein-enriched retentate. The microporousmembrane may have a filtering surface with a contact angle of no morethan about 30 degrees.

A modified oilseed material may also be formed by a process whichincludes extracting oilseed material at 20° C. to 60° C. with an aqueoussolution having a pH of 7.5 to 10.0 to form a mixture of particulatematter in an alkaline extract solution, removing at least a portion ofthe particulate matter from the mixture to form a clarified extract, andpassing the clarified extract at 55° C. to 60° C. through a filtrationsystem to produce a permeate and a protein-enriched retentate. Thefiltration system may include a microporous modified polyacrylonitrilemembrane. The microporous modified polyacrylonitrile membrane may havean MWCO of 25,000 to 500,000 and a filtering surface with a contactangle of no more than about 30 degrees.

It may be desirable for the contact time (i.e., the time period that theoilseed material is exposed to the aqueous solution) to be less that onehour. If a continuous, multistage process (e.g., a countercurrentextraction) is used, it may be advantageous for the apparent contacttime (i.e., the average time period the oilseed material is exposed tothe aqueous solution) to be no more than about one hour.

The process may further include diafiltering the protein-enrichedretentate through the filtration system to produce a protein-containingdiafiltration retentate. It may be advantageous to heat thediafiltration retentate to at least about 75° C. for a sufficient timeto form a pasteurized retentate.

The present protein supplemented dairy-type food compositions include amodified oilseed material, which typically includes at least about 85wt. % and, more desirably, at least about 90 wt. % protein on a drysolids basis.

The dairy-type food composition can include a modified oilseed materialwhich has an MW₅₀ of at least about 200 kDa, where at least about 40 wt.% of the protein in a 50 mg sample of the modified oilseed material issoluble in 1.0 mL water at 25° C.

The dairy-type food composition can include a modified oilseed materialwhich has an MW₅₀ of at least about 200 kDa and a turbidity factor of nomore than about 0.95 at 500 nm.

The dairy-type food composition can include a modified oilseed materialwhich has an MW₅₀ of at least about 200 kDa and has an NSI of at leastabout 80.

The dairy-type food composition can include a modified oilseed materialwhich has a turbidity factor of no more than about 0.95 at 500 nm, whereat least about 40 wt. % of the modified oilseed material has an apparentmolecular weight of at least 300 kDa.

The dairy-type food composition can include a modified oilseed materialwhich has an MW₅₀ of at least 200 kDa and at least 40 wt. % of theprotein in a 50 mg sample of the modified oilseed material is soluble in1.0 mL water at 25° C.

he dairy-type food composition can include a modified oilseed materialin which at least about 40 wt. % of the modified oilseed material has anapparent molecular weight of at least 300 kDa; and at least about 40 wt.% of the protein in a 50 mg sample of the modified oilseed material issoluble in 1.0 mL water at 25° C.

The dairy-type food composition can include a modified oilseed materialwhich has a bacterial load of no more than 50,000 cfu/g and a meltingtemperature of at least 87° C.

The dairy-type food composition can include a modified oilseed materialwhich is produced by a process which includes: (a) extracting oilseedmaterial with an aqueous alkaline solution to form a suspension ofparticulate matter in an oilseed extract; and (b) passing the extractthrough a filtration system including a microporous membrane to producea permeate and a protein-enriched retentate. The microporous membranecommonly has a filtering surface with a contact angle of no more than 30degrees.

The dairy-type food composition can include sugar, water and a modifiedsoybean material which generally includes at least about 90 wt. %protein on a dry solids basis. The modified oilseed material can have anMW₅₀ of at least about 400 kDa and at least about 40 wt. % of theprotein in a 50 mg sample of the modified soybean material is soluble in1.0 mL water at 25° C.

The protein supplemented sauce composition includes a modified oilseedmaterial, which typically includes at least about 85 wt. % and, moredesirably, at least about 90 wt. % protein on a dry solids basis.

The sauce composition can include a modified oilseed material which hasan MW₅₀ of at least about 200 kDa and at least about 40 wt. % of theprotein in a 50 mg sample of the modified oilseed material is soluble in1.0 mL water at 25° C.

The sauce composition can include a modified oilseed material which hasan MW₅₀ of at least about 200 kDa and a turbidity factor of no more thanabout 0.95 at 500 nm.

The sauce composition can include a modified oilseed material which hasan MW₅₀ of at least about 200 kDa and has an NSI of at least about 80.

The sauce composition can include a modified oilseed material which hasa turbidity factor of no more than about 0.95 at 500 nm, where at leastabout 40 wt. % of the modified oilseed material has an apparentmolecular weight of at least 300 kDa.

The sauce composition can include a modified oilseed material which hasan MW₅₀ of at least 200 kDa and at least 40 wt. % of the protein in a 50mg sample of the modified oilseed material is soluble in 1.0 mL water at25° C.

The sauce composition can include a modified oilseed material in whichat least about 40 wt. % of the modified oilseed material has an apparentmolecular weight of at least 300 kDa; and at least about 40 wt. % of theprotein in a 50 mg sample of the modified oilseed material is soluble in1.0 mL water at 25° C.

The sauce composition can include a modified oilseed material which hasa bacterial load of no more than 50,000 cfu/g and a melting temperatureof at least 87° C.

The sauce composition can include a modified oilseed material which isproduced by a process which includes: (a) extracting oilseed materialwith an aqueous alkaline solution to form a suspension of particulatematter in an oilseed extract; and (b) passing the extract through afiltration system including a microporous membrane to produce a permeateand a protein-enriched retentate. The microporous membrane commonly hasa filtering surface with a contact angle of no more than 30 degrees.

The sauce composition can include a suspending agent and a modifiedsoybean material which generally includes at least about 90 wt. %protein on a dry solids basis. The modified oilseed material can have anMW₅₀ of at least about 400 kDa and at least about 40 wt. % of theprotein in a 50 mg sample of the modified soybean material is soluble in1.0 mL water at 250° C.

The invention has been described with reference to various specific andillustrative embodiments and techniques. However, it should beunderstood that many variations and modifications may be made whileremaining within the spirit and scope of the invention.

1. A modified oilseed material comprising at least about 85 wt. % (dsb)protein; wherein the modified oilseed material has an MW₅₀ of at leastabout 200 kDa; and at least about 40 wt. % of the protein in a 50 mgsample of the modified oilseed material is soluble in 1.0 mL water at25° C.
 2. The modified oilseed material of claim 1 wherein the modifiedoilseed material has an EOR of no more than about 0.75 mL.
 3. Themodified oilseed material of claim 1 wherein a 13.5% aqueous solution ofthe modified oilseed material forms a gel having a breaking strength ofno more than about 25 g.
 4. The modified oilseed material of claim 1wherein the modified oilseed material has a viscosity slope of at leastabout 20 cP/min.
 5. The modified oilseed material of claim 1 wherein themodified oilseed material has a melting temperature of at least about87° C.
 6. The modified oilseed material of claim 1 wherein at leastabout 40% of the modified oilseed material has an apparent molecularweight of greater than 300 kDa.
 7. The modified oilseed material ofclaim 1 wherein the modified oilseed material has a turbidity factor ofno more than about 0.95.
 8. The modified oilseed material of claim 1wherein the modified oilseed material has a dry Gardner L value of atleast about
 85. 9. The modified oilseed material of claim 1 wherein themodified oilseed material has an NSI of at least about
 80. 10. Themodified oilseed material of claim 1 wherein the modified oilseedmaterial includes at least about 1.4 wt. % cysteine as a percentage oftotal protein.
 11. The modified oilseed material of claim 1 wherein themodified oilseed material has a latent heat of at least about 5joules/g.
 12. The modified oilseed material of claim 1 wherein themodified oilseed material has a ratio of sodium ions to a total amountof sodium, calcium and potassium ions of no more than about 0.5.
 13. Themodified oilseed material of claim 1 wherein the modified oilseedmaterial has no more than about 7000 mg/kg (dsb) sodium ions.
 14. Themodified oilseed material of claim 1 wherein the modified oilseedmaterial has a substantially bland taste.
 15. The modified oilseedmaterial of claim 1 wherein the modified oilseed material comprisesmodified soybean material.
 16. The modified oilseed material of claim 1wherein the modified oilseed material comprises at least about 90 wt. %(dsb) protein.
 17. The modified oilseed material of claim 1 wherein themodified oilseed material has a bacteria load of no more than about50,000 cfu/g.
 18. A modified oilseed material comprising at least about85 wt. % (dsb) protein; wherein at least about 40% of the modifiedoilseed material has an apparent molecular weight of greater than 300kDa; and at least about 40 wt. % of the protein in a 50 mg sample of themodified oilseed material is soluble in 1.0 mL water at 25° C.
 19. Amodified oilseed material comprising at least 85 wt. % protein on a drysolids basis wherein at least about 40% of the modified oilseed materialhas an apparent molecular weight of greater than 300 kDa; and themodified oilseed material has a viscosity slope of at least about 20.20. A modified oilseed material comprising at least 85 wt. % (dsb)protein; wherein at least about 40% of the modified oilseed material hasan apparent molecular weight of greater than 300 kDa; and at least 40wt. % of the protein in a 50 mg sample of the modified oilseed materialis soluble in 1.0 mL water at 25° C.
 21. A modified oilseed materialcomprising at least 90 wt. % (dsb) protein; wherein at least about 40%of the modified oilseed material has an apparent molecular weight ofgreater than 300 kDa; and a melting temperature of at least 87° C.
 22. Amodified oilseed material comprising at least 90 wt. % (dsb) protein;wherein at least about 40% of the modified oilseed material has anapparent molecular weight of greater than 300 kDa; and the modifiedoilseed material has an EOR of no more than about 0.75 mL.
 23. Amodified oilseed material comprising at least 90 wt. % (dsb) protein;wherein at least about 40% of the modified oilseed material has anapparent molecular weight of greater than 300 kDa; and the modifiedoilseed material has an turbidity factor of no more than about 0.95 at500 nm.
 24. A protein supplemented dairy-type food compositioncomprising a modified oilseed material, wherein the modified oilseedmaterial comprises at least 85 wt. % protein on a dry solids basis; atleast about 40 wt. % of the modified oilseed material has an apparentmolecular weight of at least 300 kDa; and at least 40 wt. % of theprotein in a 50 mg sample of the modified oilseed material is soluble in1.0 mL water at 25° C.
 25. The dairy-type food composition of claim 24wherein said dairy-type food composition is a pasteurized dairy-typefood composition.
 26. The dairy-type food composition of claim 24wherein said dairy-type food composition is a protein supplementedyogurt composition.
 27. A protein supplemented sauce compositioncomprising a modified oilseed material, wherein the modified oilseedmaterial comprises at least about 85 wt. % protein on a dry solidsbasis; and the modified oilseed material has an MW₅₀ of at least about200 kDa and at least about 40 wt. % of the protein in a 50 mg sample ofthe modified oilseed material is soluble in 1.0 mL water at 25° C. 28.The sauce composition of claim 27 wherein said sauce composition is apizza sauce.
 29. The sauce composition of claim 27 further comprising asuspending agent.